The Ancient Life History of the Earth / A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science

Amongst the Even-toed Ungulates, the great Hippopotamus major of the Pliocene still continued to exist in Post-Pliocene times in Western Europe; and the existing Wild Boar (Sus scrofa), the parent of our domestic breeds of Pigs, appeared for the first time. The Old World possessed extinct representatives of its existing Camels, and lost types of the living Llamas inhabited South America. Amongst the Deer, the Post-Pliocene accumulations have yielded the remains of various living species, such as the Red Deer (Cervus elaphus), the Reindeer (Cervus tarandus), the Moose or Elk (Alces malchis), and the Roebuck (Cervus capreolus), together with a number of extinct forms. Among the latter, the great "Irish Elk" (Cervus megaceros) is justly celebrated both for its size and for the number and excellent preservation of its discovered remains. This extinct species (fig. 264) has been found principally in peat-mosses and Post-Pliocene lake-deposits, and is remarkable for the enormous size of the spreading antlers, which are widened out towards their extremities, and attain an expanse of over ten feet from tip to tip. It is not a genuine Elk, but is intermediate between the Reindeer and the Fallow-deer. Among the existing Deer of the Post-Pliocene, the most noticeable is the Reindeer, an essentially northern type, existing at the present day in Northern Europe, and also (under the name of the "Caribou")
Fig. 264—Skeleton of the "Irish Elk" (Cervus megaceros). Post-Pliocene, Britain. in North America. When the cold of the Glacial period became established, this boreal species was enabled to invade Central and Western Europe in great herds, and its remains are found abundantly in cave-earths and other Post-Pliocene deposits as far south as the Pyrenees.

In addition to the above, the Post-Pliocene deposits of Europe and North America have yielded the remains of various Sheep and Oxen. One of the most interesting of the latter is the "Urus" or Wild Bull (Bos primigenius, fig. 265), which, though much larger than any of the existing fossils, is believed to
Fig. 265.—Skull of the Urns (Bos primigenius). Post-Pliocene and Recent. (After Owen.) be specifically undistinguishable from the domestic Ox (Bos taurus), and to be possibly the ancestor of some of the larger European varieties of oxen. In the earlier part of its existence the Urus ranged over Europe and Britain in company with the Woolly Rhinoceros and the Mammoth; but it long survived these, and does not appear to have been finally exterminated till about the twelfth century. Another remarkable member of the Post-Pliocene Cattle, also to begin with an associate of the Mammoth and Rhinoceros, is the European Bison or "Aurochs" (Bison priscus). This "maned" ox formerly abounded in Europe in Post-Glacial times, and was not rare even in the later periods of the Roman empire, though much diminished in numbers, and driven back into the wilder and more inaccessible parts of the country. At present this fine species has been so nearly exterminated that it no longer exists in Europe save in Lithuania, where its preservation has been secured by rigid protective laws. Lastly, the Post-Pliocene deposits have yielded the remains of the singular living animal which is known as the Musk-ox or Musk-sheep (Ovibos moschatus). At the present day, the Musk-ox is an inhabitant of the "barren grounds" of Arctic America, and it is remarkable for the great length of its hair. It is, like the Reindeer, a distinctively northern animal; but it enjoyed during the Glacial period a much wider range than it has at the present day, the conditions suitable for its existence being then extended over a considerable portion of the northern hemisphere. Thus remains of the Musk-Ox are found in greater or less abundance in Post-Pliocene deposits over a great part of Europe, extending even to the south of France; and closely-related forms are found in similar deposits in the United States.

Coming to the Proboscideans, we find that the Mastodons seem to have disappeared in Europe at the close of the Pliocene period, or at the very commencement of the Post-Pliocene. In the New World, on the other hand, a species of Mastodon (M. Americanus or M. Ohioticus) is found abundantly in deposits of Post-Pliocene age, from Canada to Texas. Very perfect skeletons of this species have been exhumed from morasses and swamps, and large individuals attained a length (exclusive of the tusks) of seventeen feet and a height of eleven feet, the tusks being twelve feet in length. Remains of Elephants are also abundant in the Post-Pliocene deposits of both the Old and the New World. Amongst these, we find in Europe the two familiar Pliocene species E. Meridionales and E. Antiquus still surviving, but in diminished numbers. With these are found in vast abundance the remains of the characteristic Elephant of the Post-Pliocene, the well-known "Mammoth" (Elephas primigenius), which is accompanied in North America by the nearly-allied, but more southern species, the Elephas Americanus. The Mammoth (fig. 266) is considerably larger than the largest of the living Elephants, the skeleton being over sixteen feet in length, exclusive of the tusks, and over nine feet in height. The tusks are bent almost into a circle, and are sometimes twelve feet in length, measured along their curvature. In the frozen soil of Siberia several carcasses of the Mammoth have been discovered with the flesh and skin still attached to the bones, the most celebrated of these being a Mammoth which was discovered at the beginning of this century at the mouth of the Lena, on the borders of the Frozen Sea, and the skeleton of which is now preserved at St Petersburg (fig. 266). From the occurrence of the remains of the Mammoth in vast numbers in Siberia, it might have been safely inferred that this ancient Elephant was able to endure a far more rigorous climate than its existing congeners. This inference has, however, been rendered a certainty by the specimens just referred to, which show that the Mammoth was protected against the cold by a thick coat of reddish-brown wool, some nine or ten inches long, interspersed with strong, coarse black hair more than a foot in length. The teeth of the Mammoth (fig.267) are of the type of those of the existing Indian Elephant, and are found in immense numbers in certain localities. The Mammoth was essentially northern in its
Fig. 266.—Skeleton of the Mammoth (Elephas primigenius). Portions of the integument still adhere to the head, and the thick skin of the soles is still attached to the feet. Post-Pliocene. distribution, never passing south of a line drawn through the Pyrenees, the Alps, the northern shores of the Caspian, Lake Baikal, Kamschatka, and the Stanovi Mountains (Dawkins). It occurs in the Pre-Glacial forest-bed of Cromer in Norfolk,
Fig. 267.—Molar tooth of the Mammoth (Elephas primigenius), upper jaw, right side, one-third of the natural size. a, Grinding surface; b, Side view. Post-Pliocene. survived the Glacial period, and is found abundantly in Post-Glacial deposits in France, Germany, Britain, Russia in Europe, Asia, and North America, being often associated with the Reindeer, Lemming, and Musk-ox. That it survived into the earlier portion of the human period is unquestionable, its remains having been found in a great number of instances associated with implements of human manufacture; whilst in one instance a recognisable portrait of it has been discovered, carved on bone.

Amongst other Elephants which occur in Post-Pliocene deposits may be mentioned, as of special interest, the pigmy Elephants of Malta. One of these—the Elephas Melitensis, or so-called "Donkey-Elephant"—was not more than four and a half feet in height. The other—the Elephas Falconeri, of Busk—was still smaller, its average height at the withers not exceeding two and a half to three feet.

Whilst herbivorous animals abounded during the Post-Pliocene, we have ample evidence of the coexistence with them of a number of Carnivorous forms, both in the New and the Old World. The Bears are represented in Europe by at least three species, two of which—namely, the great Grizzly Bear (Ursus ferox) and the smaller Brown Bear (Ursus arctos)—are in existence at the present day. The third species is the celebrated Cave-bear (Ursus spelœus, fig. 268), which is now extinct. The Cave-bear exceeded in its dimensions the largest of modern Bears;
Fig. 268.—Skull of Ursus spelpeus. Post-Pliocene, Europe. One-sixth of the natural size. and its remains, as its name implies; have been found mainly in cavern-deposits. Enormous numbers of this large and ferocious species must have lived in Europe in Post-Glacial times; and that they survived into the human period, is clearly shown by the common association of their bones with the implements of man. They are occasionally accompanied by the remains of a Glutton (the Gulo spelœus), which does not appear to be really separable from the existing Wolverine or Glutton of northern regions (the Gulo luscus). In addition, we meet with the bones of the Wolf, Fox, Weasel, Otter, Badger, Wild Cat, Panther, Hyæna, and Lion, &c., together with the extinct Machairodus or "Sabre-toothed Tiger." The only two of these that deserve further mention are the Hyæna and the Lion. The Cave-hyæna (Hyœna spelœa, fig. 269) is regarded by high authorities as nothing more than a variety of the living Spotted Hyæna (H. Crocuta) of South Africa. This well-known species inhabited Britain and a considerable portion of Europe during a large part of the Post-Pliocene period; and its remains often occur in great abundance. Indeed, some caves, such as the Kirkdale Cavern in Yorkshire, were dens inhabited during long periods by these animals, and thus contain the remains of numerous individuals and of successive generations of Hyænas, together with innumerable gnawed and bitten bones of their prey. That the Cave-hyæna was a contemporary with Man in Western Europe during Post-Glacial times is shown beyond a doubt by the common association of its bones with human implements.

Lastly, the so-called Cave-lion (Felis spelœa), long supposed to be a distinct species, has been shown to be nothing
Fig. 269.—Skull of Hyœna spelœa, one-fourth of the natural size. Post-Phocene, Europe. more than a large variety of the existing Lion (Felis leo). This animal inhabited Britain and Western Europe in times posterior to the Glacial period, and was a contemporary of the Cave-hyæna, Cave-bear, Woolly Rhinoceros, and Mammoth. The Cave-lion also unquestionably survived into the earlier portion of the human period in Europe.

The Post-Pliocene deposits of Europe have further yielded the remains of numerous Rodents—such as the Beaver, the Northern Lemming, Marmots, Mice, Voles, Rabbits, &c.—together with the gigantic extinct Beaver known as the Trogontherium Cuvieri (fig. 270). The great Castoroides Ohioensis of the
Fig. 270.—Lower jaw of Trogontherium Cuvieri, one-fourth of the natural size. Post-Pliocene, Britain. Post-Pliocene of North America is also a great extinct Beaver, which reached a length of about five feet. Lastly, the Brazilian bone-caves have yielded the remains of numerous Rodents of types now characteristic of South America, such as Guinea-pigs, Capybaras, tree-inhabiting Porcupines, and Coypus.

The deposits just alluded to have further yielded the remains of various Monkeys, such as Howling Monkeys, Squirrel Monkeys, and Marmosets, all of which belong to the group of Quadrumana which is now exclusively confined to the South American continent—namely, the "Platyrhine" Monkeys.

We still have very briefly to consider the occurrence of Man in Post-Pliocene deposits; but before doing so, it will be well to draw attention to the evidence afforded by the Post-Pliocene Mammals as to the climate of Western Europe at this period. The chief point which we have to notice is, that a considerable revolution of opinion has taken place on this point. It was originally believed that the presence of such animals as Elephants, Lions, the Rhinoceros, and the Hippopotamus afforded an irrefragable proof that the climate of Europe must have been a warm one, at any rate during Post-Glacial times. The existence, also, of numbers of Mammoths in Siberia, was further supposed to indicate that this high temperature extended itself very far north. Upon the whole, however, the evidence is against this view. Not only is there great difficulty in supposing that the Arctic conditions of the Glacial period were immediately followed by anything warmer than a cold-temperate climate; but there is nothing in the nature of the Mammals themselves which would absolutely forbid their living in a temperate climate. The Hippopotamus major, though probably clad in hair, offers some difficulty—since, as pointed out by Professor Busk, it must have required a climate sufficiently warm to insure that the rivers were not frozen over in the winter; but it was probably a migratory animal, and its occurrence may be accounted for by this. The Woolly Rhinoceros and the Mammoth are known with certainty to have been protected with a thick covering of wool and hair; and their extension northwards need not necessarily have been limited by anything except the absence of a sufficiently luxuriant vegetation to afford them food. The great American Mastodon, though not certainly known to have possessed a hairy covering, has been shown to have lived upon the shoots of Spruce and Firs, trees characteristic of temperate regions—as shown by the undigested food which has been found with its skeleton, occupying the place of the stomach. The Lions and Hyænas, again, as shown by Professor Boyd Dawkins, do not indicate necessarily a warm climate. Wherever a sufficiency of herbivorous animals to supply them with food can live, there they can live also; and they have therefore no special bearing upon the question of climate. After a review of the whole evidence, Professor Dawkins concludes that the nearest approach at the present day to the Post-Pliocene climate of Western Europe is to be found in the climate of the great Siberian plains which stretch from the Altai Mountains to the Frozen Sea. "Covered by impenetrable forests, for the most part of Birch, Poplar, Larch, and Pines, and low creeping dwarf Cedars, they present every gradation in climate from the temperate to that in which the cold is too severe to admit of the growth of trees, which decrease in size as the traveller advances northwards, and are replaced by the grey mosses and lichens that cover the low marshy 'tundras.' The maximum winter cold, registered by Admiral Von Wrangel at Nishne Kolymsk, on the banks of the Kolyma, is—65° in January. 'Then breathing becomes difficult; the Reindeer, that citizen of the Polar region, withdraws to the deepest thicket of the forest, and stands there motionless as if deprived of life;' and trees burst asunder with the cold. Throughout this area roam Elks, Black Bears, Foxes, Sables, and Wolves, that afford subsistence to the Jakutian and Tungusian fur-hunters. In the northern part countless herds of Reindeer, Elks, Foxes, and Wolverines make up for the poverty of vegetation by the rich abundance of animal life. 'Enormous flights of Swans, Geese, and Ducks arrive in the spring, and seek deserts where they may moult and build their nests in safety. Ptarmigans run in troops amongst the bushes; little Snipes are busy along the brooks and in the morasses; the social Crows seek the neighbourhood of new habitations; and when the sun shines in spring, one may even sometimes hear the cheerful note of the Finch, and in autumn that of the Thrush.' Throughout this region of woods, a hardy, middle-sized breed of horses lives under the mastership and care of man, and is eminently adapted to bear the severity of the climate.... The only limit to their northern range is the difficulty of obtaining food. The severity of the winter through the southern portion of this vast wooded area is almost compensated for by the summer heat and its marvellous effect on vegetation."—(Dawkins, 'Monograph of Pleistocene Mammalia.')

Finally, a few words must be said as to the occurrence of the remains of Man in Post-Pliocene deposits. That Man existed in Western Europe and in Britain during the Post-Pliocene period, is placed beyond a doubt by the occurrence of his bones in deposits of this age, along with the much more frequent occurrence of implements of human manufacture. At what precise point of time during the Post-Pliocene period he first made his appearance is still a matter of conjecture. Recent researches would render it probable that the early inhabitants of Britain and Western Europe were witnesses of the stupendous phenomena of the Glacial period; but this cannot be said to have been demonstrated. That Man existed in these regions during the Post-Glacial division of Post-Pliocene time cannot be doubted for a moment. As to the physical peculiarities of the ancient races that lived with the Mammoth and the Woolly Rhinoceros, little is known compared with what we may some day hope to know. Such information as we have, however, based principally on the skulls of the Engis, Neanderthal, Cro-Magnon, and Bruniquel caverns, would lead to the conclusion that Post-Pliocene Man was in no respect inferior in his organisation to, or less highly developed than, many existing races. All the known skulls of this period, with the single exception of the Neanderthal cranium, are in all respects average and normal in their characters; and even the Neanderthal skull possessed a cubic capacity at least equal to that of some existing races. The implements of Post-Pliocene Man are exclusively of stone or bone; and the former are invariably of rude shape and undressed. These "palæolithic" tools (Gr. palaios; ancient; lithos, stone) point to a very early condition of the arts; since the men of the earlier portion of the Recent period, though likewise unacquainted with the metals, were in the habit of polishing or dressing the stone implements which they fabricated.

It is impossible here to enter further into this subject; and it would be useless to do so without entering as well into a consideration of the human remains of the Recent period—a period which lies outside the province of the present work. So far as Post-Pliocene Man is concerned, the chief points which the palæontological student has to remember have been elsewhere summarised by the author as follows:—

1. Man unquestionably existed during the later portion of what Sir Charles Lyell has termed the "Post-Pliocene" period. In other words, Man's existence dates back to a time when several remarkable Mammals, previously mentioned, had not yet become extinct; but he does not date back to a time anterior to the present Molluscan fauna.

2. The antiquity of the so-called Post-Pliocene period is a matter which must be mainly settled by the evidence of Geology proper, and need not be discussed here.

3. The extinct Mammals with which man coexisted in Western Europe are mostly of large size, the most important being the Mammoth (Elephas primogenius), the Woolly Rhinoceros (Rhinoceros tichorhinus), the Cave-lion (Felis spelœa), the Cave-hyæna(Hyœna spelœa), and the Cave-bear (Ursus spelœus). We do not know the causes which led to the extinction of these Mammals; but we know that hardly any Mammalian species has become extinct during the historical period.

4. The extinct Mammals with which man coexisted are referable in many cases to species which presumably required a very different climate to that now prevailing in Western Europe. How long a period, however, has been consumed in the bringing about of the climatic changes thus indicated, we have no means of calculating with any approach to accuracy.

5. Some of the deposits in which the remains of man have been found associated with the bones of extinct Mammals, are such as to show incontestably that great changes in the physical geography and surface-configuration of Western Europe have taken place since the period of their accumulation. We have, however, no means at present of judging of the lapse of time thus indicated except by analogies and comparisons which may be disputed.

6. The human implements which are associated with the remains of extinct Mammals, themselves bear evidence of an exceedingly barbarous condition of the human species. Post-Pliocene or "Palæolithic" Man was clearly unacquainted with the use of any of the metals. Not only so, but the workmanship of these ancient races was much inferior to that of the later tribes, who were also ignorant of the metals, and who also used nothing but weapons and tools of stone, bone, &c.

7. Lastly, it is only with the human remains of the Post-Pliocene period that the palæontologist proper has to deal. When we enter the "Recent" period, in which the remains of Man are associated with those of existing species of Mammals, we pass out of the region of pure palæontology into the domain of the Archæologist and the Ethnologist.

LITERATURE.

The following are some of the principal works and memoirs to which the student may refer for information as to the Post-Pliocene deposits and the remains which they contain, as well as to the primitive races of mankind:—

CHAPTER XXIII.

THE SUCCESSION OF LIFE UPON THE GLOBE.

In conclusion, it may not be out of place if we attempt to summarise, in the briefest possible manner, some of the principal results which may be deduced as to the succession of life upon the earth from the facts which have in the preceding portion of this work been passed in review. That there was a time when the earth was void of life is universally admitted, though it may be that the geological record gives us no direct evidence of this. That the globe of to-day is peopled with innumerable forms of life whose term of existence has been, for the most part, but as it were of yesterday, is likewise an assertion beyond dispute. Can we in any way connect the present with the remote past, and can we indicate even imperfectly the conditions and laws under which the existing order was brought about? The long series of fossiliferous deposits, with their almost countless organic remains, is the link between what has been and what is; and if any answer to the above question can be arrived at, it will be by the careful and conscientious study of the facts of Palæontology. In the present state of our knowledge, it may be safely said that anything like a dogmatic or positive opinion as to the precise sequence of living forms upon the globe, and still more as to the manner in which this sequence may have been brought about, is incapable of scientific proof. There are, however, certain general deductions from the known facts which may be regarded as certainly established.

In the first place, it is certain that there has been a succession of life upon the earth, different specific and generic types succeeding one another in successive periods. It follows from this, that the animals and plants with which we are familiar as living, were not always upon the earth, but that they have been preceded by numerous races more or less differing from them. What is true of the species of animals and plants, is true also of the higher zoological divisions; and it is, in the second place, quite certain that there has been a similar succession in the order of appearance of the primary groups ("sub-kingdoms," "classes," &c.) of animals and vegetables. These great groups did not all come into existence at once, but they made their appearance successively. It is true that we cannot be said to be certainly acquainted with the first absolute appearance of any great group of animals. No one dare assert positively that the apparent first appearance of Fishes in the Upper Silurian is really their first introduction upon the earth: indeed, there is a strong probability against any such supposition. To whatever extent, however, future discoveries may push back the first advent of any or of all of the great groups of life, there is no likelihood that anything will be found out which will materially alter the relative succession of these groups as at present known to us. It is not likely, for example, that the future has in store for us any discovery by which it would be shown that Fishes were in existence before Molluscs, or that Mammals made their appearance before Fishes. The sub-kingdoms of Invertebrate animals were all represented in Cambrian times—and it might therefore be inferred that these had all come simultaneously into existence; but it is clear that this inference, though incapable of actual disproof, is in the last degree improbable. Anterior to the Cambrian is the great series of the Laurentian, which, owing to the metamorphism to which it has been subjected, has so far yielded but the singular Eozoön. We may be certain, however, that others of the Invertebrate sub-kingdoms besides the Protozoa were in existence in the Laurentian period; and we may infer from known analogies that they appeared successively, and not simultaneously.

When we come to smaller divisions than the sub-kingdoms—such as classes, orders, and families—a similar succession of groups is observable. The different classes of any given sub-kingdom, or the different orders of any given class, do not make their appearance together and all at once, but they are introduced upon the earth in succession. More than this, the different classes of a sub-kingdom, or the different orders of a class, in the main succeed one another in the relative order of their zoological rank—the lower groups appearing first and the higher groups last. It is true that in the Cambrian formation—the earliest series of sediments in which fossils are abundant—we find numerous groups, some very low, others very high, in the zoological scale, which appear to have simultaneously flashed into existence. For reasons stated above, however, we cannot accept this appearance as real; and we must believe that many of the Cambrian groups of animals really came into being long before the commencement of the Cambrian period. At any rate, in the long series of fossiliferous deposits of later date than the Cambrian the above-stated rule holds good as a broad generalisation—that the lower groups, namely, precede the higher in point of time; and though there are apparent exceptions to the rule, there are none of such a nature as not to admit of explanation. Some of the leading facts upon which this generalisarion is founded will be enumerated immediately; but it will be well, in the first place, to consider briefly what we precisely mean when we speak of "higher" and "lower" groups.

It is well known that naturalists are in the habit of "classifying" the innumerable animals which now exist upon the globe; or, in other words, of systematically arranging them into groups. The precise arrangement adopted by one naturalist may differ in minor details from that adopted by another; but all are agreed as to the fundamental points of classification, and all, therefore, agree in placing certain groups in a certain sequence. What, then, is the principle upon which this sequence is based? Why, for example, are the Sponges placed below the Corals; these below the Sea-urchins; and these, again, below the Shell-fish? Without entering into a discussion of the principles of zoological classification, which would here be out of place, it must be sufficient to say that the sequence in question is based upon the relative type of organisation of the groups of animals classified. The Corals are placed above the Sponges upon the ground that, regarded as a whole, the plan or type of structure of a Coral is more complex than that of a Sponge. It is not in the slightest degree that the Sponge is in any respect less highly organised or less perfect, as a Sponge, than is the Coral as a Coral. Each is equally perfect in its own way; but the structural pattern of the Coral is the highest, and therefore it occupies a higher place in the zoological scale. It is upon this principle, then, that the primary subdivisions of the animal kingdom (the so-called "sub-kingdoms") are arranged in a certain order. Coming, again, to the minor subdivisions (classes, orders, &c.) of each sub-kingdom, we find a different but entirely analogous principle employed as a means of classification. The numerous animals belonging to any given sub-kingdom are formed upon the same fundamental plan of structure; but they nevertheless admit of being arranged in a regular series of groups. All the Shell-fish, for example, are built upon a common plan, this plan representing the ideal Mollusc; but there are at the same time various groups of the Mollusca, and these groups admit of an arrangement in a given sequence. The principle adopted in this case is simply of the relative elaboration of the common type. The Oyster is built upon the same ground-plan as the Cuttle-fish; but this plan is carried out with much greater elaboration, and with many more complexities, in the latter than in the former: and in accordance with this, the Cephalopoda constitute a higher group than the Bivalve Shell-fish. As in the case of superiority of structural type, so in this case also, it is not in the least that the Oyster is an imperfect animal. On the contrary, it is just as perfectly adapted by its organisation to fill its own sphere and to meet the exigencies of its own existence as is the Cuttle-fish; but the latter lives a life which is, physiologically, higher than the former, and its organisation is correspondingly increased in complexity.

This being understood, it may be repeated that, in the main, the succession of life upon the globe in point of time has corresponded with the relative order of succession of the great groups of animals in zoological rank; and some of the more striking examples of this may be here alluded to. Amongst the Echinoderms, for instance, the two orders generally admitted to be the "lowest" in the zoological scale—namely, the Crinoids and the Cystoids—are likewise the oldest, both, appearing in the Cambrian, the former slowly dying out as we approach the Recent period, and the latter disappearing wholly before the close of the Palæozoic period. Amongst the Crustaceans, the ancient groups of the Trilobites, Ostracodes, Phyllopods, Eurypterids, and Limuloids, some of which exist at the present day, are all "low" types; whereas the highly-organised Decapods do not make their appearance till near the close of the Palæozoic epoch, and they do not become abundant till we reach Mesozoic times. Amongst the Mollusca, those Bivalves which possess breathing-tubes (the "siphonate" Bivalves) are generally admitted to be higher than those which are destitute of these organs (the "asiphonate" Bivalves); and the latter are especially characteristic of the Palæozoic period, whilst the former abound in Mesozoic and Kainozoic formations. Similarly, the Univalves with breathing-tubes and a corresponding notch in the mouth of the shell ("siphonostomatous" Univalves) are regarded as higher in the scale than the round-mouthed vegetable-eating Sea-snails, in which no respiratory siphons exist ("holostomatous" Univalves); but the latter abound in the Palæozoic rocks—whereas the former do not make their appearance till the Jurassic period, and their higher groups do not seem to have existed till the close of the Cretaceous. The Cephalopods, again—the highest of all the groups of Mollusca—are represented in the Palæozoic rocks exclusively by Tetrabranchiate forms, which constitute the lowest of the two orders of this class; whereas the more highly specialised Dibranchiates do not make their appearance till the commencement of the Mesozoic. The Palæozoic Tetrabranchiates, also, are of a much simpler type than the highly complex Ammonitidœ of the Mesozoic.

Similar facts are observable amongst the Vertebrate animals. The Fishes are the lowest class of Vertebrates, and they are the first to appear, their first certain occurrence being in the Upper Silurian; whilst, even if the Lower Silurian and Upper Cambrian "Conodonts" were shown to be the teeth of Fishes, there would still remain the enormously long periods of the Laurentian and Lower Cambrian, during which there were Invertebrates, but no Vertebrates. The Amphibians, the next class in zoological order, appears later than the Fishes, and is not represented till the Carboniferous; whilst its highest group (that of the Frogs and Toads) does not make its entrance upon the scene till Tertiary times are reached. The class of the Reptiles, again, the next in order, does not appear till the Permian, and therefore not till after Amphibians of very varied forms had been in existence for a protracted period. The Birds seem to be undoubtedly later than the Reptiles; but, owing to the uncertainty as to the exact point of their first appearance, it cannot be positively asserted that they preceded Mammals, as they should have done. Finally, the Mesozoic types of Mammals are mainly, if not exclusively, referable to the Marsupials, one of the lowest orders of the class; whilst the higher orders of the "Placental" Quadrupeds are not with certainty known to have existed prior to the commencement of the Tertiary period.

Facts of a very similar nature are offered by the succession of Plants upon the globe. Thus the vegetation of the Palæozoic period consisted principally of the lowly-organised groups of the Cryptogamous or Flowerless plants. The Mesozoic formations, up to the Chalk, are especially characterised by the naked-seeded Flowering plants—the Conifers and the Cycads; whilst the higher groups of the Angiospermous Exogens and Monocotyledons characterise the Upper Cretaceous and Tertiary rocks.

Facts of the above nature—and they could be greatly multiplied—seem to point clearly to the existence of some law of progression, though we certainly are not yet in a position to formulate this law, or to indicate the precise manner in which it has operated. Two considerations, also, must not be overlooked. In the first place, there are various groups, some of them highly organised, which make their appearance at an extremely ancient date, but which continue throughout geological time almost unchanged, and certainly unprogressive. Many of these "persistent types" are known—such as various of the Foraminifera, the Lingulœ, the Nautili, &c.; and they indicate that under given conditions, at present unknown to us, it is possible for a life-form to subsist for an almost indefinite period without any important modification of its structure. In the second place, whilst the facts above mentioned point to some general law of progression of the great zoological groups, it cannot be asserted that the primeval types of any given group are necessarily "lower," zoologically speaking, than their modern representatives. Nor does this seem to be at all necessary for the establishment of the law in question. It cannot be asserted, for example, that the Ganoid and Placoid Fishes of the Upper Silurian are in themselves less highly organised than their existing representatives; nor can it even be asserted that the Ganoid and Placoid orders are low groups of the class Pisces. On the contrary, they are high groups; but then it must be remembered that these are probably not really the first Fishes, and that if we meet with Fishes at some future time in the Lower Silurian or Cambrian, these may easily prove to be representatives of the lower orders of the class. This question cannot be further entered into here, as its discussion could be carried out to an almost unlimited length; but whilst there are facts pointing both ways, it appears that at present we are not justified in asserting that the earlier types of each group—so far as these are known to us, or really are without predecessors—are necessarily or invariably more "degraded" or "embryonic" in their structure than their more modern representatives.

It remains to consider very briefly how far Palæontology supports the doctrine of "Evolution," as it is called; and this, too, is a question of almost infinite dimensions, which can but be glanced at here. Does Palæontology teach us that the almost innumerable kinds of animals and plants which we know to have successively flourished upon the earth in past times were produced separately and wholly independently of each other, at successive periods? or does it point to the theory that a large number of these supposed distinct forms, have been in reality produced by the slow modification of a comparatively small number of primitive types? Upon the whole, it must be unhesitatingly replied that the evidence of Palæontology is in favour of the view that the succession of life-forms upon the globe has been to a large extent regulated by some orderly and constantly-acting law of modification and evolution. Upon no other theory can we comprehend how the fauna of any given formation is more closely related to that of the formation next below in the series, and to that of the formation next above, than to that of any other series of deposits. Upon no other view can we comprehend why the Post-Tertiary Mammals of South America should consist principally of Edentates, Llamas, Tapirs, Peccaries, Platyrhine Monkeys, and other forms now characterising this continent; whilst those of Australia should be wholly referable to the order of Marsupials. On no other view can we explain the common occurrence of "intermediate" or "transitional" forms of life, filling in the gaps between groups now widely distinct.

On the other hand, there are facts which point clearly to the existence of some law other than that of evolution, and probably of a deeper and more far-reaching character. Upon no theory of evolution can we find a satisfactory explanation for the constant introduction throughout geological time of new forms of life, which do not appear to have been preceded by pre-existent allied types; The Graptolites and Trilobites have no known predecessors, and leave no known successors. The Insects appear suddenly in the Devonian, and the Arachnides and Myriapods in the Carboniferous, under well-differentiated and highly-specialised types. The Dibranchiate Cephalopods appear with equal apparent suddenness in the older Mesozoic deposits, and no known type of the Palæozoic period can be pointed to as a possible ancestor. The Hippuritidœ of the Cretaceous burst into a varied life to all appearance almost immediately after their first introduction into existence. The wonderful Dicotyledonous flora of the Upper Cretaceous period similarly surprises us without any prophetic annunciation from the older Jurassic.

Many other instances could be given; but enough has been said to show that there is a good deal to be said on both sides, and that the problem is one environed with profound difficulties. One point only seems now to be universally conceded, and that is, that the record of life in past time is not interrupted by gaps other than those due to the necessary imperfections of the fossiliferous series, to the fact that many animals are incapable of preservation in a fossil condition, or to other causes of a like nature. All those who are entitled to speak on this head are agreed that the introduction of new and the destruction of old species have been slow and gradual processes, in no sense of the term "catastrophistic." Most are also willing to admit that "Evolution" has taken place in the past, to a greater or less extent, and that a greater or less number of so-called species of fossil animals are really the modified descendants of pre-existent forms. How this process of evolution has been effected, to what extent it has taken place, under what conditions and laws it has been carried out, and how far it may be regarded as merely auxiliary and supplemental to some deeper law of change and progress, are questions to which, in spite of the brilliant generalisations of Darwin, no satisfactory answer can as yet be given. In the successful solution of this problem—if soluble with the materials available to our hands—will lie the greatest triumph that Palæontology can hope to attain; and there is reason to think that, thanks to the guiding-clue afforded by the genius of the author of the 'Origin of Species,' we are at least on the road to a sure, though it may be a far-distant, victory.

APPENDIX.

TABULAR VIEW OF THE CHIEF DIVISIONS OF THE ANIMAL KINGDOM.

(Extinct groups are marked with an asterisk. Groups not represented at all as fossils are marked with two asterisks.)

INVERTEBRATE ANIMALS.

SUB-KINGDOM I.—PROTOZOA.

Animal simple or compound; body composed of "sarcode," not definitely segmented; no nervous system; and no digestive apparatus, beyond occasionally a mouth and gullet.

SUB-KINGDOM II.—CŒLENTERATA.

Animal simple or compound; body-wall composed of two principal layers; digestive canal freely communicating with the general cavity of the body; no circulating organs, and no nervous system or a rudimentary one; mouth surrounded by tentacles, arranged, like the internal organs, in a "radiate" or star-like manner.

SUB-KINGDOM III.—ANNULOIDA.

Animals in which the digestive canal is completely shut off from the cavity of the body; a distinct nervous system; a system of branched "water-vessels," which usually communicate with the exterior. Body of the adult often "radiate," and never composed of a succession of definite rings.

SUB-KINGDOM IV.—ANNULOSA.

Animal composed of numerous definite segments placed one behind the other; nervous system forming a knotted cord placed along the lower (ventral) surface of the body.

Division A. Anarthropoda. No jointed limbs.

Division B. Arthropoda or Articulata. Limbs jointed to the body.

SUB-KINGDOM V.—MOLLUSCA.

Animal soft-bodied, generally with a hard covering or shell; no distinct segmentation of the body; nervous system of scattered masses.

VERTEBRATE ANIMALS.

SUB-KINGDOM VI.—VERTEBRATA.

Body composed of definite segments arranged longitudinally one behind the other; main masses of the nervous system placed dorsally; a backbone or "vertebral column" in the majority.

GLOSSARY.

ABDOMEN (Lat. abdo, I conceal). The posterior cavity of the body, containing the intestines and others of the viscera. In many Invertebrates there is no separation of the body-cavity into thorax and abdomen, and it is only in the higher Annulosa that a distinct abdomen can be said to exist.
ABERRANT (Lat. aberro, I wander away). Departing from the regular type.
ABNORMAL (Lat. ab, from; norma, a rule). Irregular; deviating from the ordinary standard.
ACRODUS (Gr. akros, high; odous, tooth). A genus of the Cestraciont fishes, so called from the elevated teeth.
ACROGENS (Gr. akros, high; gennao, I produce). Plants which increase in height by additions made to the summit of the stem by the union of the bases of the leaves.
ACROTRETA (Gr. akros, high; tretos, pierced). A genus of Brachiopods, so called from the presence of a foramen at the summit of the shell.
ACTINOCRINUS (Gr. aktin, a ray; krinon, a lily). A genus of Crinoids.
ACTINOZOA (Gr. aktin, a ray; and zoön, an animal). That division of the Cœlenterata of which the Sea-anemones may be taken as the type.
ÆGLINA (Æglé, a sea-nymph). A genus of Trilobites.
ÆPIORNIS (Gr. aipus, huge; ornis, bird). A genus of gigantic Cursorial birds.
AGNOSTUS (Gr. a, not; gignosko, I know). A genus of Trilobites.
ALCES (Lat. alces, elk). The European Elk or Moose.
ALECTO (the proper name of one of the Furies). A genus of Polyzoa.
ALETHOPTERIS (Gr. alethes, true; pteris, fern). A genus of Ferns.
ALGÆ. (Lat. alga, a marine plant). The order of plants comprising the Sea-weeds and many fresh-water plants.
ALVEOLUS (Lat. alvus, belly). Applied to the sockets of the teeth.
AMBLYPTERUS (Gr. amblus, blunt; pteron, fin). An order of Ganoid Fishes.
AMBONYCHIA (Gr. ambon, a boss; onux, claw). A genus of Palæozoic Bivalves.
AMBULACRA (Lat. ambulacrum, a place for walking). The perforated spaces or "avenues" through which are protruded the tube-feet, by means of which locomotion is effected in the Echinodermata.
AMMONITIDÆ. A family of Tetrabranchiate Cephalopods, so called from the resemblance of the shell of the type-genus, Ammonites, to the horns of the Egyptian God, Jupiter-Ammon.
AMORPHOZOA (Gr. a, without; morphe, shape; zoön, animal). A name sometimes used to designate the Sponges.
AMPHIBIA (Gr. amphi, both; bios, life). The Frogs, Newts, and the like, which have gills when young, but can always breathe air directly when adult.
AMPHICYON (Gr. amphi, both—implying doubt; kuon, dog). An extinct genus of Carnivora.
AMPHILESTES (Gr. amphi, both; lestes, a thief). A genus of Jurassic Mammals.
AMPHISPONGIA (Gr. amphi, both; spoggos, sponge). A genus of Silurian sponges.
AMPHISTEGINA (Gr. amphi, both; stegé, roof). A genus of Foraminifera.
AMPHITHERIUM (Gr. amphi, both; therion, beast). A genus of Jurassic Mammals.
AMPHITRAGULUS (Gr. amphi, both; dim. of tragos, goat). An extinct genus related to the living Musk-deer.
AMPLEXUS (Lat. an Ambrace). A genus of Rugose Corals.
AMPYX (Gr. ampux, a wreath or wheel). A genus of Trilobites.
ANARTHROPODA (Gr. a. without; arthros, a joint; pous, foot). That division of Annulose animals in which there are no articulated appendages.
ANCHITHERIUM (Gr. agchi, near; therion, beast). An extinct genus of Mammals.
ANCYLOCERAS (Gr. agkulos, crooked; ceras, horn). A genus of Ammonitidœ.
ANCYLOTHERIUM (Gr. agkulos, crooked; therion, beast). An extinct genus of Edentate Mammals.
ANDRIAS (Gr. andrias, image of man). An extinct genus of tailed Amphibians.
ANGIOSPERMS (Gr. angeion, a vessel; sperma, seed). Plants which have their seeds enclosed in a seed-vessel.
ANNELIDA (a Gallicised form of Annulata). The Ringed Worms, which form one of the divisions of the Anarthropoda.
ANNULARIA (Lat. annulus, a ring). A genus of Palæozoic plants, with leaves in whorls.
ANNULOSA (Lat. annulus). The sub-kingdom comprising the Anarthropoda and the Arthropoda or Articulata, in all of which the body is more or less evidently composed of a succession of rings.
ANOMODONTIA (Gr. anomos, irregular; odous, tooth). An extinct order of Reptiles, often called Dicynodontia.
ANOMURA (Gr. anomos, irregular; oura, tail). A tribe of Decapod Crustacea, of which the Hermit-crab is the type.
ANOPLOTHERIDÆ (Gr. anoplos, unarmed; ther, beast). A family of Tertiary Ungulates.
ANOURA (Gr. a, without; oura, tail). The order of Amphibia comprising the Frogs and Toads, in which the adult is destitute of a tail. Often, called Batrachia.
ANTENNÆ (Lat. antenna, a yard-arm). The jointed horns or feelers possessed by the majority of the Articulata.
ANTENNULES (dim. of Antennœ). Applied to the smaller pair of antennæ in the Crustacea.
ANTHRACOSAURUS (Gr. anthrax, coal; saura, lizard). A genus of Labyrinthodont Amphibians.
ANTHRAPALÆMON (Gr. anthrax, coal; palœmon, a prawn—originally a proper name). A genus of long-tailed Crustaceans from the Coal-measures.
ANTLERS. Properly the branches of the horns of the Deer tribe (Cervidœ), but generally applied to the entire horns.
APIOCRINIDÆ (Gr. apion, a pear; krinon, lily). A family of Crinoids—the "Pear-encrinites."
APTERYX (Gr. a, without; pterux, a wing). A wingless bird of New Zealand, belong to the order Cursores.
AQUEOUS (Lat. aqua, water). Formed in or by water.
ARACHNIDA (Gr. arachne, a spider). A class of the Articulata, comprising Spiders, Scorpions, and allied animals.
ARBORESCENT. Branched like a tree.
ARCHÆOCIDARIS (Gr. archaios, ancient; Lat. cidaris, a diadem). A Palæozoic genus of Sea-urchins, related to the existing Cidaris.
ARCHÆOCYATHUS (Gr. archaios, ancient; kuathos, cup). A genus of Palæozoic fossils allied to the Sponges.
ARCHÆOPTERYX (Gr. archaios, ancient; pterux, a wing). The singular fossil bird which alone constitutes the order of the Saururœ.
ARCTOCYON (Gr. arctos, bear; kuon, dog). An extinct genus of Carnivora.
ARENACEOUS. Sandy, or composed of grains of sand.
ARENICOLITES (Lat. arena, sand; colo, I inhabit). A genus founded on burrows supposed to be formed by worms resembling the living Lobworms (Arenicola).
ARTICULATA (Lat. articulus, a joint). A division of the animal kingdom, comprising Insects, Centipedes, Spiders, and Crustaceans, characterised by the possession of jointed bodies or jointed limbs. The term Arthropoda is now more usually employed.
ARTIODACTYLA (Gr. artios, even; daktulos, a finger or toe). A division of the hoofed quadrupeds (Ungulata) in which each foot has an even number of toes (two or four).
ASAPHUS (Gr. Asaphes, obscure). A genus of Trilobites.
ASCOCERAS (Gr. askos, a leather bottle; keras, horn). A genus of Tetrabranchiate Cephalopods.
ASIPHONATE. Not possessing a respiratory tube or siphon. (Applied to a division of the Lamellibranchiate Molluscs.)
ASTEROID (Gr. aster, a star; and eidos, form). Star-shaped, or possessing radiating lobes or rays like a star-fish.
ASTEROIDEA. An order of Echinodermata, comprising the Star-fishes, characterised by their rayed form.
ASTEROPHYLLITES (Gr. aster, a star; phullon, leaf). A genus of Palæozoic plants, with leaves in whorls.
ASTRÆIDÆ (Gr. Astrœa, a proper name). The family of the Star-corals.
ASTYLOSPONGIA (Gr. a, without; stulos, a column; spoggos, a sponge). A genus of Silurian Sponges.
ATHYRIS (Gr. a, without; thura, door). A genus of Brachiopods.
ATRYPA (Gr. a, without; trupa, a hole). A genus of Brachiopods.
AVES (Lat. avis, a bird). The class of the Birds.
AVICULA (Lat. a little bird). The genus of Bivalve Molluscs comprising the Pearl-oysters.
AXOPHYLLUM (Gr. axon, a pivot; phullon, a leaf). A genus of Rugose Corals.
AZOIC (Gr. a, without; zoé, life). Destitute of traces of living beings.

BACULITES (Lat. baculum, a staff). A genus of the Ammonitidœ.
BALÆNA (Lat. a whale). The genus of the Whalebone Whales.
BALANIDÆ (Gr. balanos, an acorn). A family of sessile Cirripedes, commonly called "Acorn-shells."
BATRACHIA (Gr. batrachos, a frog). Often loosely applied to any of the Amphibia, but sometimes restricted to the Amphibians as a class, or to the single order of the Anoura.
BELEMNITIDÆ (Gr. belemnon, a dart). An extinct group of Dibranchiate Cephalopods, comprising the Belemnites and their allies.
BELEMNOTEUTHIS (Gr. belemnon, a dart; teuthis, a cuttle-fish). A genus allied to the Belemnites proper.
BELINURUS (Gr. belos, a dart; oura, tail). A genus of fossil King-crabs.
BELLEROPHON (Gr. proper name). A genus of oceanic Univalves (Heteropoda).
BELOTEUTHIS (Gr. belos, a dart; teuthis, a cuttle-fish). An extinct genus of Dibranchiate Cephalopods.
BEYRICHIA (named after Prof. Beyrich). A genus of Ostracode Crustaceans.
BILATERAL. Having two symmetrical sides.
BIMANA (Lat. Bis, twice; manus, a hand). The order of Mammalia comprising man alone.
BIPEDAL (Lat. bis, twice; pes, foot). Walking upon two legs.
BIVALVE (Lat. bis, twice; valvœ, folding-doors). Composed of two plates or valves; applied to the shell of the Lamellibranchiata and Brachiopoda, and to the carapace of certain Crustacea.
BLASTOIDEA (Gr. blastos, a bud; and eidos, form). An extinct order of Echinodermata, often called Pentremites.
BRACHIOPODA (Gr. brachion, an arm; pous, the foot). A class or the Molluscoida, often called "Lamp-shells," characterised by possessing two fleshy arms continued from the sides of the mouth.
BRACHYURA (Gr. brachus, short; oura, tail). A tribe of the Decapod Crustaceans with short tails (i.e., the Crabs).
BRADYPODIDÆ. (Gr. bradus, slow; podes, feet). The family of Edentata comprising the Sloths.
BRANCHIA (Gr. bragchia, the gill of a fish). A respiratory organ adapted to breathe air dissolved in water.
BRANCHIATE. Possessing gills or branchiæ.
BRONTEUS (Gr. broné, thunder—an epithet of Jupiter the Thunderer). A genus of Trilobites.
BRONTOTHERIUM (Gr. bronté, thunder; therion beast). An extinct genus of Ungulate Quadrupeds.
BRONTOZOUM (Gr. bronté, thunder; zoön, animal). A genus founded on the largest footprints of the Triassic Sandstones of Connecticut.
BUCCINUM (Lat. buccinun, a trumpet). The genus of Univalves comprising the Whelks.

CAINOZOIC (See Kainozoic.)
CALAMITES (Lat. calamus, a reed). Extinct plants with reed-like stems, believed to be gigantic representatives of the Equisetaceœ.
CALCAREOUS (Lat. calx, lime). Composed of carbonate of lime.
CALICE. The little cup in which the polype of a coralligenous Zoophyte (Actinozoön) is contained.
CALYMENE (Gr. kalumené, concealed). A genus of Trilobites.
CALYX (Lat. a cup). Applied to the cup-shaped body of a Crinoid (Echinodermata).
CAMAROPHORIA (Gr. kamara, a chamber; phero, I carry). A genus of Brachiopods.
CAMELOPARDALIDÆ. (Lat. camelus, a camel; pardalis, a panther). The family of the Giraffes.
CANINE (Lat. canis, a dog). The eye-tooth of Mammals, or the tooth which is placed at or close to the præmaxillary suture in the upper jaw, and the corresponding tooth in the lower jaw.
CARAPACE. A protective shield. Applied to the upper shell of Crabs, Lobsters, and many other Crustacea. Also the upper half of the immovable case in which the body of a Chelonian is protected.
CARCHARODON (Gr. karcharos. rough; odous, tooth). A genus of Sharks.
CARDIOCARPON (Gr. kardia, the heart; karpos, fruit). A genus of fossil fruit from the Coal-measures.
CARDIUM (Gr. kardia, the heart). The genus of Bivalve Molluscs comprising the Cockles. Cardinia, Cardiola, and Cardita have the same derivation.
CARNIVORA (Lat. caro, flesh; voro, I devour). An order of the Mammalia. The "Beasts of Prey."
CARNIVOROUS (Lat. caro, flesh; voro, I devour). Feeding upon flesh.
CARYOCARIS (Gr. karua, a nut; karis, a shrimp). A genus of Phyllopod Crustaceans.
CARYOCRINUS (Gr. karua, a nut; krinon, a lily). A genus of Cystideans.
CAUDAL (Lat. cauda, the tail). Belonging to the tail.
CAVICORNIA (Lat. cavus, hollow; cornu, a horn). The "hollow-horned" Ruminants, in which the horn consists of a central bony "horn-core" surrounded by a horny sheath.
CENTRUM (Gr. kentron, the point round which a circle is described by a pair of compasses). The central portion or "body" of a vertebra.
CEPHALASPIDÆ. (Gr. kephale, head; aspis, shield). A family of fossil fishes.
CEPHALIC (Gr. kephale, head). Belonging to the head.
CEPHALOPODA (Gr. kephale; and podes, feet). A class of the Mollusca, comprising the Cuttle-fishes and their allies, in which there is a series of arms ranged round the head.
CERATIOCARIS (Gr. keras, a horn; karis, a shrimp). A genus of Phyllopod Crustaceans.
CERATITES (Gr. keras, a horn). A genus of Ammonitidœ.
CERATODUS (Gr. keras, a horn; odous, tooth). A genus of Dipnoous fishes.
CERVICAL (Lat. cervix, the neck). Connected with or belonging to the region of the neck.
CERVIDÆ (Lat. cervus, a stag). The family of the Deer.
CESTRAPHORI (Gr. kestra, a weapon; phero, I carry). The group of the "Cestraciont Fishes," represented at the present day by the Port-Jackson Shark; so called from their defensive spines.
CETACEA (Gr. ketos, a whale). The order of Mammals comprising the Whales and the Dolphins.
CETIOSAURUS (Gr. ketos, whale; saura, lizard). A genus of Deinosaurian Reptiles.
CHEIROPTERA (Gr. cheir, hand; pteron, wing). The Mammalian order of the Bats.
CHEIROTHERIUM (Gr. cheir, hand; therion, beast). The generic name applied originally to the hand-shaped footprints of Labyrinthodonts.
CHEIRURUS (Gr. cheir, hand; oura, tail). A genus of Trilobites.
CHELONIA (Gr. cheloné, a tortoise). The Reptilian order of the Tortoises and Turtles.
CHONETES (Gr. choné or choané, a chamber or box). A genus of Brachiopods.
CIDARIS (Lat. a diadem). A genus of Sea-urchins.
CLADODUS (Gr. klados, branch; odous, tooth). A genus of Fishes.
CLATHROPORA (Lat. clathti, a trellis; porus, a pore). A genus of Lace-corals (Polyzoa).
CLISIOPHYLLUM (Gr. klision, a hut; phullon, leaf). A genus of Rugose Corals.
CLYMENIA (Clumene, a proper name). A genus of Tetrabranchiate Cephalopods.
COCCOSTEUS (Gr. kokkos, berry; osteon, bone). A genus of Ganoid Fishes.
COCHLIODUS (Gr. kochlion, a snail-shell; odous, tooth). A genus of Cestraciont Fishes.
CŒLENTERATA (Gr. koilos, hollow; enteron, the bowel). The sub-kingdom which comprises the Hydrozoa and Actinozoa. Proposed by Frey and Leuckhart in place of the old term Radiata, which included other animals as well.
COLEOPTERA (Gr. koleos, a sheath; pteron, wing). The order of Insects (Beetles) in which the anterior pair of wings are hardened, and serve as protective cases for the posterior pair of membranous wings.
COLOSSOCHELYS (Gr. kolossos, a gigantic statue; chelus, a tortoise). A huge extinct Land-tortoise.
COMATULA (Gr. koma, the hair). The Feather-star, so called in allusion to its tress-like arms.
CONDYLE (Gr. kondulos, a knuckle). The surface by which one bone articulates with another. Applied especially to the articular surface or surfaces by which the skull articulates with the vertebral column.
CONIFERÆ (Lat. conus, a cone; fero, I carry). The order of the Firs, Pines, and their allies, in which the fruit is generally a "cone" or "fir-apple."
CONULARIA (Lat. conulus, a little-cone). An extinct genus of Pteropods.
COPRALITES (Gr. kopros, dung; lithos, stone). Properly applied to the fossilised excrements of animals; but often employed to designate phosphatic concretions which are not of this nature.
CORALLITE. The corallum secreted by an Actinozoön which consists of a single polype; or the portion of a composite corallum which belongs to, and is secreted by, an individual polype.
CORALLUM (from the Latin for Red Coral). The hard structures deposited in, or by the tissues of an Actinozoön,—commonly called a "coral."
CORIACEOUS (Lat. corium. hide). Leathery.
CORYPHODON (Gr. korus, helmet; odous, tooth). An extinct genus of Mammals, allied to the Tapirs.
CRANIUM (Gr. kranion, the skull). The bony or cartilaginous case in which the brain is contained.
CRETACEOUS (Lat. creta, chalk). The formation which in Europe contains white chalk as one of its most conspicuous members.
CRINOIDEA (Gr. krinon, a lily; eidos, form). An order of Echinodermata, comprising forms which are usually stalked, and sometimes resemble lilies in shape.
CRIOCERAS (Gr. krios, a ram; keras, a horn). A genus of Ammonitidœ.
CROCODILIA (Gr. krokodeilos, a crocodile). An order of Reptiles.
CROSSOPTERYGIDÆ. (Gr. krossotos, a fringe; pterux, a fin). A sub-order of Ganoids in which the paired fins possess a central lobe.
CRUSTACEA (Lat. crusta, a crust). A class of Articulate animals, comprising Crabs, Lobsters, &c., characterised by the possession of a hard shell or crust, which they cast periodically.
CRYPTOGAMS (Gr. kruptos, concealed; gamos, marriage). A division of plants in which the organs of reproduction are obscure and there are no true flowers.
CTENACANTHUS (Gr. kteis, a comb; akantha, a thorn). A genus of fossil fishes, named from its fin-spines.
CTENOID (Gr. kteis, a comb; eidos, form). Applied to those scales of fishes the hinder margins of which are fringed with spines or comb-like projections.
CURSORES (Lat. curro, I run). An order of Aves, comprising birds destitute of the power of flight, but formed for running vigorously (e.g., the Ostrich and Emeu).
CUSPIDATE. Furnished with small pointed eminences or "cusps."
CYATHOCRINUS (Gr. kuathos, a cup; krinon, a lily). A genus of Crinoids.
CYATHOPHYLLUM (Gr. kuathos, a cup; phullon, a leaf). A genus of Rugose Corals.
CYCLOID (Gr. kuklos, a circle; eidos, form). Applied to those scales of fishes which have a regularly circular or elliptical outline with an even margin.
CYCLOPHTHALMUS (Gr. kuklos, a circle; ophthalmos, eye). A genus of fossil Scorpions.
CYCLOSTOMI (Gr. kuklos, and stoma, mouth). Sometimes used to designate the Hag-fishes and Lampreys, forming the order Marsipobranchii.
CYPRÆA (a name of Venus). The genus of Univalve Molluscs comprising the Cowries.
CYRTOCERAS (Gr. kurtos. crooked; keras, horn). A genus of Tetrabranchiate Cephalopods.
CYSTIPHYLLUM (Gr. kustis, a bladder; phullon, a leaf). A genus of Rugose Corals.
CYSTOIDEA (Gr. kustis, a bladder; eidos, form). The "Globe-crinoids," an extinct order of Echinodermata.