Essays on the Microscope / Containing a Practical Description of the Most Improved Microscopes, a General History of Insects, etc., etc.

The seed of the musk scabious is beautiful in its shape and structure. The calix or cup which contains the seed is of an octagonal form, and makes an appearance like a fine vase, having scallopped edges, and toward the inner part of the edge a white ruffled membrane. The ribs run down from its mouth, which is bell-fashioned, and becoming narrower downward, form obtuse angles by continuing from the bend to form the bottom of the vase. Between these ribs, down to the beginning of the narrow part, it is clear, though not wholly transparent, and from thence to the bottom the ribs are hairy. This vase contains the seed, wherein appears first its thick body, which runs up with a narrow neck, till it divides into five spiculated fibres, whose spiculæ are determined upwards, and are thereby prepared to cause the seed to recede from any thing that might injure it on being touched. The bodies of the vases, when first ripe, are of a fine lemon yellow, but grow by long keeping darker; and the bason formed by the roots of the minute fibres is of a fine green, but the fibres themselves of a shining brown, like brown sugar-candy, as their spines are also.

These, and a number of similar beauties in this part of the creation, are described at large by Dr. Parsons, in his work entitled, “The Microscopic Theatre of Seeds.”[149] Most kinds of seeds should be prepared for a microscopical examination by steeping them in warm water till their coats are separated, and their seminal leaves may then be opened without laceration. But seeds, while dry, and without any preparation, are of an almost infinite variety of shapes, and afford a number of pleasing objects for the microscope.

One of the most interesting scenes in microscopical botany is exhibited in mouldiness. Those miniature plants seem to bear the same relation to the vegetable kingdom that the animalcula infusoria do to the animal; they were formerly considered as shapeless and unformed masses, but we now view them with surprize and pleasure taking their place in the great scale of organized beings, and presenting us with some of the most striking characteristics of vegetables.

OF TRANSPARENT OBJECTS.

We may select from the elytra, or upper wings of beetles, many beautiful objects, the construction of these will be found to differ very much; the membranaceous wings, as in the scarabæus solstitialis or small cock-chaffer; blatta Americana or cockroach; all the grylli, as locusts, grasshoppers, &c. Among the cicadas, the elytra of the nervosa are the most elegant, the nerves are elevated, and curiously spotted with brown. The elytra of the cimices or field bugs, which are a very numerous tribe, afford a great variety of objects; we may select from these as the most beautiful the elytra of the cimex baccarum and the cimex striatus, Plate XX. Fig. 1. The elytra of the fulgora candelaria, from China, differ essentially from all others.

The under or more transparent wings of beetles excite our attention even more than the upper or crustaceous ones; for whether we consider the delicacy of their texture, the great weight that many of them are calculated to sustain in the air, or the very curious manner in which they fold them up under the upper case, their mechanism must astonish and delight us; no two genera will be found alike, though every individual of the same genus will be exact. The wing of the forficula auricularia or earwig, Plate XIV. is an elegant specimen of the manner of their folding; this wing folds under a case not one-eighth of its size.

The under wing of the blatta orientalis, or beetle common in most kitchens, appears to unite the elytra and transparent wings, partaking in some degree of both.

Among the membranaceous or more transparent winged insects, the variety is endless, each genus differing essentially from the other; some appearing full of membranes or nerves, curiously disposed; others, again, with scarce any, like a clear piece of talc or isinglass; some exhibit a curious ground-work of points, which on close examination prove short hairs, while the nerves of others are furnished with little scales or feathers, as in some species of the gnat. The wings of many muscæ are coloured with black, brown, and white, in clouds, spots, stripes, &c. &c.

The libellulæ or dragon-flies alone afford a great variety, not only in form but colour; these are all furnished with numerous and very strong nerves, adapted to the velocity of their flight. The wings of the ephemera or may-flies, are much more delicate, these flies rest with their wings erect. The phryganeæ differ very much from the foregoing, and also from one another; their under wings fold, and their upper ones are of a stronger texture, many of them so much resembling small moths as not easily to be distinguished from them: these are all found in the vicinity of ponds and marshy places. In the hemerobii a wonderful degree of elegance is exhibited in the disposition of the nerves which compose their wings, each nerve being adorned with hair in a beautiful manner; there are many species of these flies equally beautiful, a specimen is given in Plate XV. The ichneumon fly has four transparent wings, the inferior ones smaller, and more delicate than the superior; the tube through which the female deposits its eggs is an additional object well worth attention. The wings of wasps are folded longitudinally; the wings of the large bee are very curious. Gnats in general, and the various species of tipulæ, together with the clouded and variegated wings of the muscæ, tabani, &c. increase the catalogue beyond the power of enumeration; in short, there is not a wing but has its particular beauties, and will amply repay the attentive observer. The currant sphinx moth connects the transparent and farinaceous wings, partaking of both; the white plumed, and many-plumed moths, exhibit wings totally different from all the rest; many other small moths furnish wings sufficiently transparent for observation, the fringe or edges being remarkably beautiful.

OF THE PULEX IRRITANS, OR COMMON FLEA.

Many small insects that are not too opake, may be viewed and examined as transparent objects; some of these having been particularly noticed by the early microscopic writers, it will be necessary to enumerate a few of them, as without it the work might be deemed incomplete. Every one is acquainted with the agility and blood-thirsty disposition of the flea, of the caution with which it comes to the attack, and the readiness with which it avoids pursuit. It belongs to the class aptera, has two eyes, six feet particularly constructed for leaping, the antennæ or feelers are filiform, or rather moniliform; the rostrum is inflected, setaceous, and armed with a sting; the belly is compressed. This creature is produced from eggs, which it deposits on the animals that afford it food, or affixes them to the wool of blankets, rugs, &c. These eggs in about a week are hatched into small larvæ or worms, which are of a whitish colour, with a slight tinge of reddish, and adhere closely to the body of the animal, or other substance on which they are produced; in a fortnight they come to a tolerable size, and are very lively and active; but if they be touched, they roll themselves up in a ball. At this period they prepare themselves for their pupa or chrysalis state, by inclosing themselves in a loosely-spun web, or diffused envelopement of a very soft, silky, or rather cotton-like appearance, and of a white colour. In this the larva changes into a chrysalis, out of which in about twelve days emerges the animal in its perfect state, armed with powers to disturb the peace of an emperor, and occasion uneasy sensations in the fairest bosom.[150]

It is difficult to obtain such a view of the flea, as will display the mechanism and apparatus belonging to the head; these parts are but imperfectly represented in the celebrated drawing of Dr. Hooke in his Micrographia. The neck is long, finely arched, and much resembles the tail of a lobster; the body is covered all over with a polished suit of sable armour, formed of a hard shelly substance, curiously jointed and folded over one another, and yet yielding to all the nimble motions of the little animal; the edges of the scales are curiously set with short spikes or hairs: it has two sharp eyes to look before it leaps, for which purpose its legs are excellently adapted, having three large joints in each, besides several smaller ones. These joints are so contrived, that it can as it were fold them up one within another; in leaping, they all spring at once, and the whole strength of the insect is exerted. The flexure of the fore legs is forward, that of the hind legs backward. They are all very hairy, and terminated by two long hooked sharp claws; the two fore legs are placed very near the neck, and often conceal the proboscis from our view, the other four join all at the breast: the proboscis or sucker with which it penetrates the skin, is placed at the end of the snout, and is not easily seen except the two fore legs are first removed; in it are included a couple of darts or lancets, which, after the proboscis has made an entrance, are thrust farther into the flesh, and make the blood flow from the adjacent parts, occasioning that round red spot, with a hole in the center of it, called a flea-bite.

OF THE CIMEX LECTULARIUS, OR BED BUG.

Various are the antipathies of mankind, but all appear to unite in their dislike to this animal and the louse, and to detest them as their natural and nauseous enemies. The bug “intrudes upon the peace of mankind, and often banishes that sleep which even anxiety and sorrow permitted to approach: the night is the season when the bed bug issues from its retreat to make its depredations; by day it lurks in the most secret parts of the bed, takes the advantage of every chink and cranny to make a secure lodgement, and contrives its habitation with so much art, that scarce any industry can discover its retreat; but when darkness promises security, it then issues from every corner of the bed, drops from the tester, and crawls from behind the arras, and travels to the unhappy patient, who vainly wishes for rest and refreshment.”

Linnæus is of opinion that this insect is not originally of European growth, but was imported from some other country. It is not only disagreeable on account of the extremely offensive smell proceeding from it, but also because of the rapidity with which it increases, and the voraciousness of its appetite. It has two brown small prominent eyes, two antennæ, and a crooked proboscis, which lies close under the breast. Instead of wings, we find on the first ring of the belly two flat pieces which entirely cover it, and extend towards the sides. These plates, the trunk, and the head, are amply set with hairs. The proboscis is divided transversely into four parts, which are probably so many articulations; this piece is best seen on the under side of the bug, being bent flat on the belly, and reaching half way down the body; but the mechanism of this, as well as other parts of these minute insects, cannot be perfectly understood, but by an accurate examination with the microscope. It has six legs, each of which has three joints; these legs, like those of the fly, are formed for running, not leaping; the skin is shagreened, and the separation of the rings usually marked by a smooth shining band. On the belly, at a small distance from the edge, a set of circular spots may be perceived, two on each ring, except the last; these are the spiracula. Examined internally, we find one large artery, a stomach, and intestines. The instant it perceives the light, it endeavours to gain its obscure habitation, and seldom fails in making good its retreat.

OF THE PEDICULUS HUMANUS, OR LOUSE.

“Whenever wretchedness, disease, and hunger seize upon man, the louse seldom fails to add itself to the tribe, and to increase in proportion to the number of his calamities.”

When the human louse is examined with the microscope, its deformity fills us with disgust. In the head we may distinguish two fine black eyes, looking backward and fenced with hair; near these are the two antennæ, each of which has five joints set with short bristles; the fore-part of the head is rather long, the hinder more round or obtuse; there is a small part that projects from the nose or snout, this serves as a sheath or case to the proboscis or piercer, which the creature thrusts into the skin to draw out the blood and humours which are its destined food, for it has no mouth which opens in the common way.

This proboscis has been estimated to be seven-hundred times smaller than a hair; it is contained in another case within the first, and can be drawn in or thrust out at pleasure; the skin is hard and transparent. From the under side proceed six legs, each of which has five joints, and terminates in two unequal hooked claws, these it uses as we would a thumb and finger; there are hairs between the claws, as well as all over the legs; the body finishes in a cloven tail, which is generally covered, and partly concealed by hairs.

From the extreme transparency of its skin, the internal parts may be seen to greater advantage than in any other insect; as, the various ramifications of the veins and arteries, in which a kind of regular pulsation may be observed, as well as the peristaltic motion of the intestines, which is continued from the stomach to the tail. When the louse feeds, the blood rushes like a torrent into the stomach, moving with so strong a propulsion and contraction, as appears very curious. The digestive powers are so great, that the colour of the blood changes in its passage from thick and black at its first entrance, to a fine ruby colour in the intestines, and nearly white in the veins. Its greediness is so great, that the excrement contained in the intestines is ejected at the same time, to make room for this new supply. There is scarce any animal that multiplies so fast as this unwelcome intruder; the moment it is excluded from the egg it begins to breed.

It would be endless to describe the various creatures which go under the name of lice, and swarm upon every part of nature. The reader, desirous of a more particular account of those which infest various animals, will obtain full satisfaction, by consulting Rhedi’s Treatise de Generatione Insectorum.

OF THE ARANEA, OR SPIDER.

The spider is another insect which is often examined with the microscope, and certainly affords much matter for observation. “Formed for a life of rapacity, and incapable of living but by blood, all its habits are calculated to deceive and surprize; it spreads toils to entangle its prey; it is endued with patience to expect its coming, and is possessed of arms and strength to destroy it when fallen into the snare.”

The eyes of the spider have been described in page 199, they are a very beautiful microscopic object, viewed either as transparent or opake. The spider has eight legs with three joints, thickly beset with hairs, and terminating in three crooked moveable claws, which have little teeth like a saw; at a small distance from these claws, but placed higher up, is another something like a cock’s spur, by the assistance of which it adheres to its webs; but the weapon wherewith it seizes and kills its prey is a pair of sharp crooked claws or forceps placed in the fore-part of the head. The insect can open or extend these pincers as occasion may require; when undisturbed, it suffers them to lie one upon another, concealed in two cases constructed for their reception. Leeuwenhoeck says, that each of these claws has a small aperture or slit, through which he supposes a poisonous juice is injected into the wound it makes.

The exuvia, or cast-off skin of the spider, which may be found in cobwebs, being transparent, is an excellent object; and the fangs or forceps may be more easily separated from it, and examined with greater exactness than in a living subject. The contexture of the spider’s web, and the manner of weaving it, have been discovered by the microscope. The spider is supplied with a large quantity of glutinous matter within its body, and five tubercles or nipples for spinning it into thread, of what size it pleases, either by opening or contracting the sphincter muscles. This substance, when examined accurately, will be found twisted into many coils, of an agate colour, and which from its tenacity may be easily drawn out into threads. The five nipples are placed near the extremity of the tail; from these the aforesaid substance proceeds; it adheres to any thing against which it is pressed, and being drawn out hardens in the air. The threads unite at a small distance from the body, so that those which appear to us so fine and single, are, notwithstanding, composed of five joined together, and these are many times doubled when the web is in formation. The web serves him for the double purpose of an habitation and of a machine for catching his food; for in the center of this web it dwells in dismal solitude, like a dragon in his lonely den, an image of the evil one, wasting all things round about it, and eager to destroy every appearance of life. When first hatched, even these loathsome insects seem endued with a principle of association, spinning a web in common; but this connection is of short duration, and soon terminates by their destroying one another. If, like the silk-worm, they were disposed to live together peaceably, it is possible that their labours might be productive of advantages nearly similar to that valuable insect; for which purpose repeated attempts have been made, though they proved ineffectual.

OF THE CULEX, OR GNAT.

The gnat is a beautiful object for the microscope. The curious manner in which it disposes its eggs upon the surface of the water has been noticed in page 288. From the egg proceeds the larva, in which state it is most happily suited to shew the several operations of life; for a moderate magnifying power will discover what passes within its transparent body. It has a large scaly head, with two large antennæ, besides several hairy parts, and articulated bristles near the mouth, which are in continual motion. If the worm be dissected, the feet of the gnat may be found folded up in the divisions of the thorax; the abdomen is divided into eight rings, from the edges of each of which three or four bristles proceed. The tail is divided into two parts of very different forms; by one of these it can steer itself in any direction; in the other, two pulmonary tubes may be discovered, through which the insect breathes. The larva has a power of moistening the tail with an oleaginous liquor, by which means it can suspend itself on the surface of the water. On agitating the water, the worms descend with precipitation to the bottom; but they soon return to the surface, to breathe the air through the tube that is annexed to their tail. From this state, they pass into that of the pupa, which is the gnat enclosed in a third skin, under which it is formed and strengthened; the organs of respiration are changed, breathing at this period through a couple of horns, which are placed near the head, keeping itself rolled upon the surface of the water, though on the least motion it unrolls itself and descends, aided by the oars near the tail.

From the spoils of the pupa, a little winged insect proceeds, whose every part is active to the highest degree, and whose entire structure is the just object of our admiration. Its head, adorned with feathers, is a fine microscopic object; but the proboscis may be deemed one of the most curious instruments in the insect creation. This formidable apparatus has been particularly described in page 187.

The exuviæ or cast-off skins of insects, being exceedingly transparent, are well adapted for observation, as they exhibit the external appearance of the little animal; among these, may be reckoned those of spiders and cimices, but particularly the forficula auricularia or earwig, which is an elegant exuvia; a magnified view of the beautiful wing of this insect is exhibited in Plate XIV. and described in page 205. The stings of insects vary not only in their form, but also in their apparatus; most of them require dissection; as the stings, for they have generally two, are inclosed in a hard sheath or case, to which is added a pair of feelers. The stings of bees, wasps, &c. are barbed, while those of the chrysis are serrated, or notched like a saw. The head of insects is furnished with an instrument or proboscis various as the insects themselves, but all meriting attention, as being admirably adapted to their different uses and purposes. Among the most remarkable are those of the bed bug, flea, gnat, empis, conops, &c. to which may be added the singular one of the tabanus, described in page 188, and figured in Plate XVI. A description of the apparatus of the bee has also been given in page 181, and of that of the butterfly in page 186.

The antennæ of moths, butterflies, and most other insects, display as great beauty in their formation as they are endless in their variety; the distinguishing characters of many of them have been described in pages 190-193, and that of the lepas anatifera in particular in page 345, and exhibited in Plate XIII.

The eyes of insects are singularly constructed, but this structure is not discoverable without the assistance of the microscope; the eyes of the libellula are hexagonal, see Plate XVI. Fig. 3, and their description in page 195; those of the lobster are square, as exhibited in Fig. 5 of the same plate, and described in page 197.

The hair of animals, as the mouse, goat, large bee, and many species of caterpillars, particularly the tufts on the head and tail of the larva of the phalæna antiqua, offer many beauties to the curious observer. The bristles of a hog, cut transversely, appear tubular, and the root of hair is evidently bulbous.

The muscular fibres, and every anatomical preparation that can be brought under the microscope, are pleasing objects; the reader will meet with many curious and interesting observations on the hairs, the muscles, nerves, and other parts of the human body, in Fontana’s Treatise on the Venom of Vipers.

The legs of all insects appear very much diversified, and their mechanism truly astonishing, according with their different occupations, as particularized in pages 210-212.

Scales of fish, as soles, roach, dace, salmon, eels, &c. as also the scales of snakes, lizards, &c. &c. Specimens of scales are given in Plates X. and XIX. The scales form a light, but at the same time a solid and smooth covering to the fish; they hinder the fluid from penetrating the body, for which purpose they are laid in a kind of natural oil; they serve also as a protection, and break the force of any accidental blow, which may be the reason why river-fish have larger and stronger scales than sea-fish, being more liable to accidents.

The purple tide of life, nay the very globules of the blood, may be seen distinctly rolling through veins and arteries smaller than the finest hair.[151]

Feathers, and parts of feathers of birds, are not to be passed by or unnoticed; but it is impossible to point out any of these in preference to others, as each has its peculiar beauties; the plumulæ of these have generally in the microscope the appearance of large feathers; the pith contained in the quill, if cut transversely and examined, exhibits an admirable reticular texture. Many other parts of birds will afford a great variety of curious objects, particularly the egg: Mr. Martin says, that the internal spongy substance of bones may be better observed in those of birds, than of any other animal; even the feathers or scales of a moth’s wing amply repay the observer; these also vary in their texture and figure; but the largest and most commonly applied, are from the body of the sphinx stellatarum, or humming-bird moth; a specimen is given in Plate XVI. Fig. E F H I.

Transverse sections of all kinds of wood, especially those of a pithy or soft nature, form some of the most delightful objects for the microscope; among these, the section of fern root will be found strikingly curious, from the singular disposition of the air and sap vessels; their beauty will be seen by the figures in Plates XXVIII. XXIX. and XXX.

Flowers, whose brilliancy and variety constitute one of the principal beauties of nature, each being distinguished from the rest by some peculiar beauty or shining character.

The flowers of most grasses, with all the varieties of mosses; the farina of flowers; mouldiness, which evidently appears to vegetate; all the kinds of sponge; sea-weeds; particularly the confervæ, which are jointed like a cane. The extensive family of corallines present an elegant appearance; the most beautiful are the sea hair, sea fir, sickle, fox tail, &c. described by Ellis.

Dissected leaves, which shew the fibres and nerves; the human intestine injected with wax is a fine object; as are many other anatomical preparations. The seed of the silver-rind birch appears like an insect; seed of the quaking grass is also much admired, as is the leaf which covers the seed of sorrel. Among artificial productions, the edge of a razor, and point of a fine needle, as also fine cambrick, evidently discover the inferiority of the workman; particles from the collision of flint and steel; wire melted by the electric explosion, and other articles innumerable.

Besides these, there is an immense variety of objects which can only be satisfactorily examined alive, such as polypes, minute aquatic insects; animalcula of various infusions, as eels in paste, vinegar, &c. The eyes and teeth of snails; the circulation of the blood in the tails of fishes, &c.[152]

CHAP. XI.
AN ARRANGEMENT AND DESCRIPTION OF MINUTE AND RARE SHELLS.—A DESCRIPTIVE LIST OF A VARIETY OF VEGETABLE SEEDS, AS THEY APPEAR WHEN VIEWED BY THE MICROSCOPE. BY THE EDITOR.

Notwithstanding the abundance of objects which have from time to time afforded delight to the attentive and diligent microscopic observer, little doubt can be entertained but that amidst the immense variety of minute shells, as well as the seeds of vegetables, numbers remain unexplored, though highly meriting notice.

With the hope of exciting the attention of the curious toward these subjects, and affording hints to those who may happily possess inclination, together with leisure and opportunity to pursue the inquiry, I shall enumerate to the reader a few specimens of each of these admirable productions of nature; towards the elucidating of which, very little, comparatively, has as yet been done.

As far as my knowledge extends, the first author who has treated on the subject of minute and rare shells, is Plancus, who published a treatise in quarto, at Venice, in the year 1739, with the title “De Conchis Ariminensibus minus notis;” a third and improved edition of which appeared in 1760. It is a very curious and learned work, containing a natural history of testaceous animals of Rimini, an Italian town situated on the Adriatic shore; and more particularly of minute nautili.

In the year 1784, Mr. Walker of Faversham published in quarto a collection of minute shells, which was the joint production of himself and William Boys, Esq. F. S. A. of Sandwich, in Kent, assisted by the late Edward Jacob, Esq. F. S. A. It contains an arrangement and concise description of ninety shells, accompanied with neatly engraved figures of the whole series; the greater part of them as well in their magnified state, as that in which they appear to the naked eye. Specimens of those which are esteemed most curious and rare, I have selected from this work: a reference to the original will afford the reader more complete satisfaction, and possibly animate him to further pursuits.

This publication appeared in so favourable a light to that eminent patron of science, Sir Joseph Banks, that I should accuse myself of unjustifiable remissness, were I to neglect this opportunity of introducing an extract from the copy of a letter addressed by him to the late Mr. Jacob, which is now in my possession.

“We” (the Royal Society) “are all much obliged to you for the pains you have taken in bringing this work to light. Natural history is, I am convinced, more benefited by a thin volume of real new facts, which is the case in yours, than by a folio of comments generally written by those who mean to receive praise, more founded on the elegance with which they express the ideas they conceive, than on any prospect of utility to be derived from the ideas themselves. From such naturalists, De Buffon, &c. good Lord deliver our honest science.”

That truly amiable, and no less intelligent lady, the late Duchess Dowager of Portland, likewise expressed her approbation of the work in a letter to Mr. Boys.

By this publication, a number of shells, heretofore unknown, are added to the British conchology, sufficient to shew that the path is now laid open and made easy of access to inquisitive naturalists in different parts of the kingdom for still greater discoveries. Indeed, it is rather extraordinary, that the authors of this country, who have so advantageously applied the microscope to a variety of objects in the animal kingdom, should have neglected to examine the shores of our own seas, crowded as they are with objects equally worthy of their investigation. Baker’s observation in his “Employment for the Microscope,” p. 244, is entitled to more attention than has been paid to it. “Shell-fish,” says he, “are objects that have as yet been very slightly examined by the microscope, and therefore the serious inquirer into nature’s secret operations may here be certain of discovering beauties, which at present he can have no conception of.” But thus it is, nature opens her rich and inexhaustible treasures by slow degrees to the inquisitive mind of man. In fact, different observers have generally different pursuits, otherwise these objects would scarcely have escaped the attention of many ingenious naturalists, particularly the quick-sighted Mr. Ellis, who has so clearly investigated and described the corals and corallines of the adjacent coasts.

To those who have perused the treatise of Plancus, already mentioned, it is necessary to observe, that though the sand on our coasts contain a vast variety of specimens, yet it by no means appears so productive as the sand of Rimini; lest, despairing of success in their first researches, they may be induced to desist from further examination. Every parcel will, however, be found to contain some of the more common shells.

It may not be improper here to point out to future inquirers the mode of facilitating the discovery of these minute objects. The sand being perfectly dried, put a handful on an open sheet of paper, and by gently shaking it from side to side, the minute shells, being specifically lighter than the sand, will be separated from, and lie on its surface, and will thus be more expeditiously procured than by any other method. It is also adviseable to place the objects intended for inspection in a situation secured from any sudden blast of air, otherwise, owing to their levity, they may be unexpectedly blown away, and a loss sustained of some of the rarer specimens; even incautiously breathing on them, or coughing, may be productive of similar disagreeable effects.

The following observations by an ingenious critic[153] are so apposite, and so perfectly coincident with my own sentiments on the subject, that I cannot resist the impulse I feel to enable the reader to partake of the pleasure which I have experienced in their perusal.

“Let not the minuteness of the objects here delineated call up the surly inquiries of those, who have not been accustomed to live with their eyes open to the works of nature: they are not fit judges in these matters. If they will persist in asking, Of what use is all this labour? What good can accrue to mankind from this knowledge, in point of food, or other use? We know of none at all, either present or likely to happen, as to the body, for use or ornament, or to the satisfying any appetite: nevertheless, a much nobler idea will take its rise in our opinion; one which, by displaying so momentously the power of the omniscient Creator, will thwart the infidel in his favourite ideas of escaping the eyes of the Almighty, and force him, as he descends the scale from the more immense objects to these minutissima, to confess, that the being which has formed these, can fully equal all that the tongue of man has yet declared of the possibility of his power. For, what a train of wonders have we here to pursue? What must be the œconomy of animals so very diminutive, so weak, so exposed from their situation to the force of every rude wave, and who, notwithstanding, so often escape unhurt? How do they rear their young? From whence collect their prey?”

A DESCRIPTION AND ARRANGEMENT OF MINUTE AND RARE SHELLS.[154]

SERPULA.
THE WORM-SHELL.

Serpula Bicornis.

Plate XIV. Fig. 2. S. bicornis ventricosa. The bellied semilunar worm-shell.

The colour white, opake, and glossy. From Sandwich and Reculver, though not common.

Serpula Perforata.

Fig. 3. S. bicornis umbilico perforato. The semilunar perforated worm-shell.

The colour white, opake, and glossy. From Sandwich: very rare.

Serpula Lactea.

Fig. 4. S. tenuis ovalis lævis. The thin, smooth, egg-shaped worm-shell.

The colour pellucid, with milky veins. From Sandwich: not common.

Serpula Lagena Sulcata.

Fig. 5. S. (lagena) striata sulcata rotunda. The round striated and furrowed flask worm-shell.

The colour whitish, transparent, and glossy. From Sandwich, Reculver, and Shepey: very rare.

Serpula Retorta.

Fig. 6. S. (retorta) rotunda marginata cervice curvatim exerto. The marginated retort worm-shell.

The colour white and opake. From Sandwich: not common.

Serpula Incurvata.

Fig. 7. S. recta anfractibus tribus contiguis regulariter involutis. The straight horn worm-shell, with three close intorted spires at the tip.

The colour white, semitransparent. From Sandwich: rare.

This shell, though resembling the semilituus of Linnæus, p. 1163, No. 280, is not of the genus of Nautilus, having neither syphon in the aperture, nor the internal concamerated structure.

DENTALE.
THE TOOTH-SHELL.

Dentalium Imperforatum.

Fig. 8. D. apice imperforata transverse striatum. The imperforated transversely striated tooth-shell.

The colour white and opake. From Sandwich: not very common.

PATELLA.
THE LIMPET.

Patella Rota.

Fig. 9. P. plana orbiculata margine regulariter dentato. The toothed-wheel limpet.

The colour white and opake. From Sandwich: extremely rare.

HELIX.
THE DEPRESSED SNAIL.

Helix Carinata.

Fig. 10. H. striata apertura compressa tribus anfractibus carinata. The striated suboval-mouthed snail, of three spires and a sharp edge.

The colour light brown pellucid. In a fresh water stream, near Faversham.

Helix Spinosa.

Fig. 11. H. subglobosa umbilicata ore subrotundo margine spinoso. The roundish mouth deeply umbelicated snail with a thorny margin.

The colour brown pellucid. From Bysing Wood, near Faversham: exceeding rare.

Helix Reticulata.

Fig. 12. H. unici anfractus subumbilicata apertura rotunda marginata eleganter reticulata. The round mouthed reticulated single spired slightly subumbilicated snail.

The colour white and pellucid. From Reculver: extremely rare.

Helix Striata.

Fig. 13. H. striata apertura subovali anfractibus supradorsalibus. The oval mouthed striated snail with the spires reflected on the back.

The colour greenish, white pellucid. From Sandwich: very rare.

TURBO.
THE PRODUCED SNAIL.

Turbo Reticulatus.

Fig. 14. T. subumbilicatus quatuor anfractibus reticulatis apertura subrotunda. The slightly umbilicated turbo with four reticulated spires, and a roundish aperture.

The colour white and pellucid. From Seasalter: very rare.

Turbo Eburneus.

Fig. 15. T. quinque anfractibus ventricosis apertura subrotunda. The five spired ventricose turbo with a roundish mouth.

The colour white and opake. From Reculver: very rare.

Turbo Strigatus.

Fig. 16. T. tribus anfractibus primo strigis tribus transversis apertura subovata. The three spired turbo, the first spire with three transverse ridges and a suboval aperture.

The colour opake white. From Seasalter: very rare.

Turbo Albidus.

Fig. 17. T. turritus septem anfractibus strigatis apertura ovali. The taper turbo with seven ridged spires and an oval aperture.

The colour opake white. From Sandwich: rare.

Turbo Carinatulus.

Fig. 18. T. turritus carinatus septem anfractibus apertura coarctata marginata. The taper carinated turbo with seven spires and a contracted marginated aperture.

The colour opake white. From Sandwich: very rare.

Turbo Clathratulus.

Fig. 19. T. clathratus sex anfractibus apertura ovali marginata. The barred six spired turbo with an oval marginated aperture.

The colour opake white. From Sandwich: exceeding rare.

Turbo Crassus.

Fig. 20. T. crassus clathratus quinque anfractibus apertura rotunda marginata. The thick barred turbo of five spires and a round marginated aperture.

The colour opake white. From Sandwich: very rare.

Turbo Punctatus.

Fig. 21. T. turritus perversus novem anfractibus punctatis apertura coarctata. The reversed taper turbo of nine dotted spires and straitened aperture.

The colour light-brown opake. From Sandwich: not common.

Turbo Shepeianus.

Fig. 22. T. sex anfractibus reticulatis apertura ovali submarginata. The six spired reticulated turbo with an oval submarginated aperture.

The colour semipellucid white. From Shepey island: very rare.

Turbo Sandvicensis.

Fig. 23. T. tribus anfractibus reticulatis apertura unidentata. The three spired elegantly reticulated turbo with a one toothed oval aperture.

The colour pellucid white. From Sandwich: exceeding rare.

TROCHUS.
THE TOP-SHELL.

Trochus Fuscus.

Fig. 24. T. umbilicatus quinque anfractibus marginatus apertura subrotunda. The five spired umbilicated marginated top-shell with a roundish aperture.

The colour opake brown. From Sandwich: common.

BUCCINUM.
THE WHILK.

Buccinum Obtusulum.

Fig. 25. B. ampullaceum tribus anfractibus apertura ovali. The bellied whilk of three spires with an oval aperture.

The colour opake white. From Faversham Creek: very rare.

Buccinum Longiusculum.

Fig. 26. B. turritum quinque anfractibus apertura ovali. The taper whilk of five spires with an oval aperture.

The colour white semipellucid and glossy. In Faversham Creek only; but not uncommon there.

VOLUTA.
THE VOLUTE.

Voluta Alba.

Fig. 27. V. alba opaca longitudinaliter striata. The white opake volute. From Sandwich and Shepey island: not uncommon.

This shell resembles Mr. Pennant’s voluta Jonensis, but differs in the form of the aperture, as well as in the size.

BULLA.
THE DIPPER.

Bulla Regulbiensis.

Fig. 28. B. crassa apertura medio coarctata. The thick dipper, with a compressed aperture.

The colour white and opake. From Reculver: very rare.

NAUTILUS.
THE CHAMBERED NAUTILUS.

Nautilus Beccarii.

Fig. 29. N. spiralis umbilicatus geniculis insculptis. The spiral umbilicated nautilus with deep joints.

The colour, while the fish is alive, is a fine pellucid crimson; when dead, is white. It is found alive on the fucus vesiculosus, and is a very common shell on all the coast, and seems to be an universal litoral one, by the numbers found at Rimini, and in the sand of the South Seas.

Lin. S. N. p. 1162, No. 276. Nautilus Beccarii. Planch. Tab. 1. Fig. 1. Gualtier, Tab. 19. Fig. H, H, I.

Nautilus Crispus.

Fig. 30. N. spiralis geniculis crenatis. The spiral nautilus with crenated joints.

The colour opake white. The finest specimens are from Shepey: not uncommon.

Lin. S. N. p. 1162, No. 275. crispus. Planch. T. 1. f. 2. Gualt. T. 19. f. A. D.

Nautilus Calcar.

Fig. 31. N. spiralis apertura lineari geniculis elevatis. The spiral nautilus, with a narrow aperture and raised joints.

The colour opake white. From Shepey island: not common.

Lin. S. N. 1162, No. 274, calcar. Pl. T. 1. f. 3, 4. Gualt. T. 19. f. C. B.

Nautilus Lævigatulus.

Fig. 32. N. spiralis geniculis lævibus. The spiral nautilus with smooth joints.

The colour semipellucid, white and glossy. From Sandwich and Seasalter: not common.

Nautilus Depressulus.

Fig. 33. N. spiralis utrinque subumbilicatus geniculis depressis plurimis. The spiral subumbilicated nautilus, with many depressed joints.

The colour opake white. From Reculver: very rare.

Nautilus Umbilicatulus.

Fig. 34. N. spiralis umbilicatus geniculis sulcatis. The umbilicated spiral nautilus, with furrowed joints.

The colour opake white. From Sandwich: not common.

Nautilus Crassulus.

Fig. 35. N. spiralis crassus utrinque umbilicatus geniculis lineatis. The thick spiral doubly umbilicated nautilus, with fine joints.

The colour opake white. From Reculver: exceeding rare.

Nautilus Lobatulus.

Fig. 36. N. spiralis lobatus anfractibus supra rotundatis subtus depressioribus. The spiral lobated nautilus, with the spires rounded on the upper side, and depressed on the under.

The colour opake white. From Whitstable: not common.

Nautilus Carinatulus.

Fig. 37. N. oblongus carinatus apertura lineari ovali. The oblong carinated nautilus, with a narrow oval aperture.

The colour whitish, transparent like glass. From Seasalter and Sandwich: very rare.

Nautilus Subarcuatulus.

Fig. 38. N. subarcuatus geniculis exertis. The bending nautilus with raised joints.

The colour opake brown. From Shepey island: very rare.

MYTILUS.
THE MUSCLE.

Mytilus Phaseolus.

Fig. 39. M. lævis valvulis antice inflexis. The smooth muscle, with the valves inflected in front.

The colour brown and glossy. From a fresh water stream near Faversham: common.

Mytilus Punctatulus.

Fig. 40. M. subrhombiformis punctatus. The subrombic dotted muscle.

The colour pellucid white. From Sandwich: common.

Mytilus Discors.

Fig. 41. M. discors areis tribus distinctis. The divided muscle.

The colour opake brown. From Sandwich: not common.

Lin. S. N. 1159, No. 261. Da Costa Br. Conch, p. 221. Tab. 17. f. 1. where it is exactly described, and as badly engraved.

ANOMIA.
THE SCALE.

Anomia Squamula.

Fig.42. A. squamula. The scale anomia.

The colour opake white and glossy. From Sandwich: not uncommon.

Lin. S. N. 1151, No. 221. This shell is well described by Da Costa; but neither he, or Mr. Pennant, have caused it to be engraved.

ARCA.
THE ARC.

Arca Modiolus.

Fig. 43. A. oblonga striata antice angulata. The oblong striated arc, with the foreside angulated.

The colour opake white. From Sandwich: not uncommon.

Lin. S. N. p. 1141, No. 171. Arca Modiolus.

CARDIUM.
THE COCKLE.

Cardium Muricatulum.

Fig. 44. C. subcordatum antice muricatum. The heart cockle, with the front muricated.

The colour opake white. From Shepey island: not uncommon.

LEPAS.
THE ACORN-SHELL.

Lepas Strigatulus.

Fig. 45. L. balanus striatus apertura obliqua. The striated acorn-shell, with an oblique aperture.

The colour light brown. From Sandwich, on the roots of sea-weeds, the finest specimens on lobsters: not uncommon.

ECHINUS.
THE SEA-URCHIN.

Echinus Lobatulus.

Fig. 46. E. subrotundus planus lobatus. The flat roundish lobated echinus.

The colour opake white. From Reculver: rare.

ASTERIAS.
THE STAR-FISH.

Asterias Triradiata.

Fig. 47. A. triradiata lævis. The smooth three-rayed star-fish.

The colour white, transparent as glass. On all the different shores that have been examined.

Having thus described a few specimens of those pleasing microscopical objects, minute shells, I shall agreeably to the intimation given in the note to page 613, proceed to

A DESCRIPTIVE LIST OF A VARIETY OF VEGETABLE SEEDS.[155]