Fig. 1. A large, discoidal echinite, of the type called Clypeus or Shield-echinus, (Clypeus sinuatus, of Leske,) from the Coral Rag of Oxfordshire. This species abounds in the beds of this division of the Oolite in Berkshire, Wiltshire, Gloustershire, &c.

Fig. 2. "Echinanthites orbicularis (Pygurus) of Leske."—Mr. Parkinson.

Fig. 3. An imperfect flint cast of an echinus (Discoidea), from the South Downs.

Fig. 4. The Helmet Echinite, (Ananchytes ovatus, of Lamarck,) from the Chalk of Kent. This is a characteristic species of the white chalk, and abounds in the strata of the North and South Downs. At Northfleet, near Gravesend, the quarry-men find beautiful specimens.

Fig. 5. An oval echinite (Nucleolites,) from Verona.

Fig. 6. A portion of a very flat echinite, in which the rays or ambulacra are in a floriform arrangement, (Echinodiscus bisperforatus, of Parkinson; Lobophora biperforata, of Desor,) from Tertiary Strata, Verona.

Fig. 7. A small discoidal echinite (Discoidea subuculus, of Leske,) from the upper greensand of Warminster.

Fig. 8. The floriform radiated part of the shell of an echinite (Clypeaster), from the tertiary strata of Malta.

Fig. 9. A cast in flint of part of the interior of the case or shell of an echinite.

Fig. 10. An elegant conical echinite (Conulus albogalerus, of Leske; Galerites, of Agassiz), common in the chalk of Kent and Sussex.

Fig. 11. View of the base of fig. 10, showing the situation of the two apertures of the shell.

Fig. 1. The shell of a Turban Echinite (Cidaris saxatilis, of Parkinson), broken in two, and each piece imbedded in the same fragment of flint. From Kent.

Fig. 2. A round Buckler Echinite (Echinodiscus (Clypeaster) subrotundus, of Parkinson), from Italy.

Fig. 3. The upper surface of an Echinite (Spatangites (Disaster, of Agassiz) ovalis, of Parkinson); from Scarborough.

Fig. 4. View of the upper, and fig. 5, of the lower surface of an Echinite, (Spatangus (Hemipneaster, of Agassiz) radiatus, of Parkinson,) from the cretaceous strata of St. Peter's Mountain, Maestricht.

Fig. 6. A small Echinite (Echinites (Nucleolites, of Leske) pyriformis, of Parkinson), from the cretaceous strata of Maestricht.

Fig. 7. A small Echinite of a different genus (Echinites (Cassidulus, of Lamarck,) Lapis cancri, of Parkinson), from Maestricht.

Fig. 8. An Echinite (Spatangites (Nucleolites) brissoides ovalis, of Parkinson). Locality unknown.

Fig. 9. A beautiful specimen of a large heart-shaped Echinite of a recent species (Spatangus purpureus), from a modern tertiary deposit, Malta.

Fig. 10. An Echinite (Echinodiscus (Clypeaster) laganum, of Parkinson), from a tertiary deposit, Verona.

Fig. 11. This Is a very abundant Spatangus or heart-shaped echinite, (Spatangus cor marinum, of Parkinson; Cor testudinarium, of Goldfuss; Micraster cor anguinum, of Agassiz,) in the chalk of Kent, and some parts of Sussex. Siliceous casts, forming cordiform flints, with deep imprints of the pentapetalous rays on the vertex, are common among the stones of the ploughed fields of the Downs.

Fig. 12. A Spatangite, (Spatangus (Micraster, of Agassiz) lacunosus, of Parkinson), from tertiary strata, Malta,

Fig. 1. A fragment of the shell of a Turban Echinite, with three clavated or club-shaped spines attached, on chalk, from Kent (Cidaris claviger, of König). The inner surface of the fragment of shell is exposed.

Fig. 2. A crushed shell of an elegant species of Turban Echinite (Cidaris sceptrifera, of Mantell), on a block of chalk; with two displaced spines near it. The sceptre-like form of the spines suggested the specific name. The chalk has been carefully cut away so as to display the shell and spines as much as possible without detaching them. From Sussex; common in the chalk near Gravesend.

Fig. 3. Part of the shell, with two spines of another species (Cidaris vesiculosus, of Goldfuss), from Kent.

Fig. 4. "A fossil echinital spine resembling a belemnite."—Mr. Parkinson. I am unable to determine either the species or locality of this fossil: it is indeed doubtful whether it is a spine of an echinus.

Figs. 5 to 19, represent various kinds of echinital spines of Turban Echinites or Cidarites.

Fig. 5. "A fossil spine named 'Bacolo di Santo Paulo,' by Scilla."—Mr. Parkinson. From Verona.

Figs. 6, 8, 9, 10, 11, 14, 15, 16, 17, & 18, are, I believe, referable to various species of Cidaris that occur in the Oolite or Jurassic deposits.

Figs. 9 and 11. Species of Cidaris glandiferus, of Goldfuss.

Fig. 15, is a well known form, which occurs in thousands in the Oolite Limestone, the Coral Rag, of Caen, and other localities in Wiltshire; it belongs to a beautiful Cidarite (Cidaris Blumenbachii[51]), which is occasionally found with similar spines attached.

Fig. 12. "A flat serrated spine from Verona."—Mr. Parkinson. It belongs to the Cidaris Schmidelii, of Goldfuss.

Fig. 7. The interior of the upper part or vertex of a large Echinus, from the tertiary strata of Malta. The greater portion of the shell is broken away, but a small fragment showing the outer surface remains on the upper left hand of the specimen. The five large petalous ambulacra are beautifully seen. Perfect examples of this echinite (Echinanthus Clypeaster altus, of Parkinson), are not uncommon.

Fig. 19. A spine of Cidaris sceptrifera, from the chalk of Kent.

Fig. 20. An elegant Turban Echinite, (Hemicidaris crenularis, of Lamarck,) common in the Coral Rag of Wiltshire. Groups of this beautiful echinoderm, with numerous spines attached, are found at Caen. I have seen on one slab of limestone, upwards of twenty individuals with the spines radiating round the shell, as if the animals were alive on a mud bank in shallow water.

Fig. 21. A fragment of the shell with two spines (Cidaris claviger), attached to a flint; from Kent.

Figs. 1, & 3. Upper and under view of a discoidal spiral univalve shell (Euomphalus pentangulatus, of Sowerby), from the mountain limestone of Derbyshire. The extinct genus Euomphalus, a name suggestive of the deeply excavated disk, comprises many species which occur in the Silurian, Devonian, and Carboniferous formations. The shell has chambers, or rather obsolete cavities sealed up by a shelly partition, in the abandoned part of the spire.[52]

Fig. 2. An elegant univalve shell, completely silicified or transmuted into flint (Natica canrena, of Parkinson, Natica Gentii, of Sowerby), from the upper greensand of Blackdown.

Figs. 4, & 6. Two views of the same specimen; a univalve (Nerita conoidea, of Lamarck), in which the apex or upper part is destroyed, and the interior of the shell is filled with yellowish brown chalcedony; in fig. 4, a cast of the spire is seen, and in fig. 6, the mouth of the shell, with the chalcedony partially filling up the interior. From tertiary strata near Paris.

Fig. 5. A beautiful fossil univalve shell, from the "Red Crag" of Suffolk, known to collectors as the "Essex reversed whelk," from the spire being coiled in the opposite direction to the common mode; the mouth is consequently situated to the left of the observer; the same species occurs with the spire in the usual direction. This shell is the Murex (Fusus) contrarius, of Parkinson.

Figs. 7, & 8. Under and upper view of another species of Euomphalus (E. rugosus, of Sowerby), from the Wenlock limestone, Dudley.

Fig. 9. An enlarged view of fig. 10. "A shell of the genus Sigaretus."—Mr. Parkinson. Mr. Morris thinks it is merely an operculum of a small univalve.

Fig. 11. A chambered cephalopodous shell (Lituites lituus, of Hisinger), from Silurian strata, Sweden.

Figs. 12, & 13. These curious contorted bodies are named "Vermiculitæ" by Mr. Parkinson. They occur in the cream-coloured limestone of Pappenheim and Solenhofen. They are termed "Lumbricaria colon" by Goldfuss; and "Cololites" by M. Agassiz; the last-named eminent naturalist has demonstrated that they are the fossilized intestines of fishes.[53]

Fig. 1. "Part of a hexahedral Serpulite."—Mr. Parkinson.

Fig. 2. A silicified mass of delicate filiform serpulæ, from the upper greensand of Devonshire (Serpula filiformis, of Sowerby).

Fig. 3. Portion of a species of Siliquaria, from tertiary strata, France. It is the shell of an Annelide related to Dentalium.

Fig. 5. A spiral Serpulite (it resembles the Serpula conica); probably from the cretaceous beds of the Isle of Rugen.

Fig. 6, is a piece of polished sandstone, from the upper greensand of Wiltshire, "the markings on which are produced by sections of a species of Serpula (Vermetus concavus, of Sowerby)."—Mr. Morris.

Fig. 7. A species of Vermetus; from Bayonne?

Figs. 8, & 9. A species of Vermetus which abounds in the coarse arenaceous limestone of Bognor Rocks, in Sussex (Vermetus Bognoriensis, of Sowerby).

Fig. 10. "A section of the shell of a Nautilus, to show that the siphuncle sometimes suffered distension."—Mr. Parkinson.

Fig. 11. A species of Serpula (Serpula ampullacea, of Sowerby), from the chalk of Kent.

Fig. 12. A fragment of the back or dorsal part of the shell of a fossil Nautilus (Nautilus centralis, of Sowerby), from the London clay, Brentford. The outer shell is broken away, and the siphuncle, traversing five of the septa of the chambers, is exposed.

Fig. 13. "The outline of the back of a Nautilus."—Mr. Parkinson.

Fig. 14. An Orthoceratite (Orthoceras annulatum, of Sowerby; O. undulatum, of Kissinger), from the Wenlock Limestone, Dudley.

Fig. 15. A fragment of a fossil Nautilus (Nautilus Parkinsoni, of Mr. Edwards), from the London clay of Harwich. It shows the situation of the siphuncle and the form of the septa, as indicated by the sinuous transverse lines.

Fig. 16. A polished section of a Nautilus (N. truncatus, of Sowerby), from the Inferior Oolite of Yeovil, Somersetshire. The chambers are filled up with crystalline limestone, with the exception of the six outermost cells, in which are left hollows that are lined with calcareous spar.

Fig. 17. Polished section of an Orthoceratite, from the Silurian strata of Oëland, Sweden.

Fig. 18. The discoidal part of a Lituite from the same locality as fig. 17.

Fig. 19. a polished slab of grey marble, from the Devonian formation of the Rhine. The figures are sections of Orthoceratites, a; and Lituites, b.

Fig. 1. A fossil shell named Hippurite (Hippurites bioculatus, of D'Orbigny), from the south of France. This shell belongs to a family termed Rudistes, whose characters are somewhat problematical,—some naturalists referring them to the bivalves, and others to the univalves. The Hippurite is generally of an elongated conical form, and has internally two obtuse longitudinal ridges; the base is sometimes partitioned by transverse septa.

Fig. 5, is a longitudinal section of a specimen in which septa are displayed. The aperture is closed by a moveable operculum, or upper valve, as in the specimen fig. 1. The substance of the shell is cellular and very thick, and when fractured, resembles that of the lamelliferous corals. Some kinds attain a large size, and are called "petrified horns" by the inhabitants of the districts in the Pyrenees where they abound. Though Hippurites are abundant in the chalk of the south of France, and in Spain and Portugal, none have been found in England. The Spherulite, a nearly allied genus, which has no internal longitudinal ridges, occurs in the chalk of Sussex: it was first discovered near Lewes. (Spherulites Mortoni, of Mantell.)[54]

Fig. 2. The siphuncle of a very large Orthoceratite ("related to the genus Ormoceras," Mr. Morris), from the Rhine.

Figs. 3 & 4, "show the direction in which the siphuncle in Orthoceratites intersects the septa."

Fig. 6. Siphuncle of an orthoceratite (related to Orthoceras duplex, of Kissinger), from the Silurian strata, Sweden.

Fig. 7. An Orthoceratite (O. pyriforme, of Sowerby), from the Silurian strata, Dudley.

Figs. 8-15. Various kinds of Belemnites.

Fig. 8. "A Belemnite of large size," Mr. Parkinson. This specimen is part of the phragmocone from near the lower apical portion, partially invested with the fibrous rostrum or guard. It is the species named Belemnites giganteus by M. D'Orbigny; from the Oxford clay of Wiltshire.

Fig. 9. The guard of a Belemnite, eroded by some Annelide.

Fig. 10, is a vertical section of a fragment of a Belemnite, showing the alveolus or cavity for the reception of the apex of the phragmocone in the upper part.

Fig. 11. The distal or apical part of the rostrum or guard of a Belemnite. The annexed outline of a transverse section exhibits the radiated structure.

Fig. 12. The distal part of the guard of a chalk Belemnite (Belemnitella mucronata); from Norwich. Siliceous casts of the phragmocone of Belemnitella are occasionally met with in the flints of the South Downs. This phragmocone has a longitudinal flat band or ridge, extending down the dorsal aspect: the chambers are very numerous; the slit or fissure in the ventral aspect of the guard, is occupied by a thin expansion of the phragmocone.

Fig. 13. A Belemnite from the great oolite of Stonesfield (Belemnites fusiformis, of Parkinson). The upper part shows the alveolus for the reception of the apex of the phragmocone.

Fig. 14. A fragment of a guard split vertically, the flat surface showing a section of the alveolus filled with spar. This specimen belongs to the Belemnites cylindriformis, of Parkinson.

Fig. 15. a Belemnite (Belemnites coniformis, of Parkinson), having part of the guard broken off, to show the alveolus or hollow in which the apical part of the phragmocone is received. The removed portion has the cast of the alveolus attached to it.

Fig. 16, of which fig. 17, is an enlarged view, is a species of chambered foraminiferous shell, called Nodosaria (N. raphanistrum, of Lamarck); from Sienna. See description of Plate LXII.

Fig. 1. A Belemnite (Belemnitella mucronata) attached to a flint. Kent.

Fig. 2. Cast of part of a straight-chambered shell (Baculites Fraujasii, of Lamarck), in which the septa, or partitions, are deeply and regularly sinuated. In fossils of this kind, the cast of each chamber is distinct from the others; but the series is held together by the flexuosities of the septa. From Maestricht.

Fig. 3. A limestone cast of the chamber of an Ammonite: from Bath. The elongated channel in the middle indicates the position of the siphuncle.

Fig. 4. Fragment of an Ammonite, showing cavities of two chambers, and the canal of the siphuncle, partly lined with calcareous spar.

Fig. 5. Polished sections of an Ammonite (Ammonites Walcotii) from the Lias, Whitby. The chambers are filled with semi-transparent spar. The siphunculus is seen running along the dorsal, or outer margins of the volutions. The dark appearances observable in several parts of the siphuncle result from the carbonization of the animal membrane with which the tube was lined in the living state.

Fig. 6. "An Oval Ammonite."—Mr. Parkinson. This is evidently the cast of a discoidal shell pressed into an elliptical form. In the Chalk-marl, casts of Ammonites, Nautilites, &c. are very commonly more or less distorted by compression. The marl appears to have remained in a plastic state after the decomposition of the shell in which it was moulded, and to have admitted of being squeezed into close contact with the surrounding matrix; when the stratum became consolidated the cast retained its accidental shape, and adhering but slightly to the investing marl, was separable by a properly directed blow. This explains the otherwise unintelligible fact of a cast being closely invested by the rock, and all traces of the shell in which it was formed absent. When both the cast and the matrix became solid and uncompressible before the shell was decomposed, then loose casts were formed; as is common in the Portland stone, &c. The fossil figured appears to be an indifferent example of a common chalk-marl species (Ammonites Mantelli, of Sowerby).

Fig. 7. A beautiful cast of an Ammonite, in which the foliaceous septa transmuted into pyrites (sulphuret of iron, or marcasite), are exquisitely shown.

Fig. 8. A very fine specimen of an Ammonite (Ammonites latus, of Sowerby), from the "Galt;" a subdivision of the Lower chalk, in which Ammonites, with their pearly shells beautifully preserved, are abundant. From Folkstone, in Kent; a celebrated locality for these and other fossils of the same cretaceous deposits.

Fig. 9. Sections of a pyritous cast of an Ammonite, showing the sinuous edges of the septa.

Fig. 1. Part of the cast of a species of Hamite (Hamites intermedius, of Sowerby), from the Gait of Folkstone. The name Hamites was employed by Mr. Parkinson to designate a genus of chambered shells, in which the direction of the spire, instead of being straight, as in Baculites, or discoidal, as in Ammonites, was bent like a hook beyond the inner reflected part. All the specimens here figured are but fragments.[55]

Figs. 2, & 5. Portions of Hamites intermedius, of Sowerby.

Fig. 3. Hamites plicatilis, of Sowerby.

Fig. 4. A fragment of Hamites rotundus, of Sowerby.

Figs. 6, & 7. Two views of a species of an extinct genus, the shells of which, though not chambered, are supposed to have been inhabited by Cephalopoda, like the recent Argonaut. The specimen (Bellerophon costatus, of Sowerby) is from the Mountain limestone of Derbyshire.[56]

Figs. 8, & 9. An Ammonite with a contracted aperture, and three deep constrictions across the disk. From the Inferior oolite of Normandy.

Figs. 10, & 11. Two specimens of "Scaphites, or Boat-like Ammonite," of Mr. Parkinson. A remarkable cretaceous genus of extinct cephalopoda. The specimens figured are from the Lower chalk of Sussex (Scaphites costatus, of Mantell; S. equalis, of Sowerby).

Fig. 12. Cast of a spiral chambered shell, called Turrilite, of which many species occur in the lower cretaceous strata (Turrilites costatus, of Langius). The quarries of lower chalk at St. Catharine's Mount, near Rouen, in Normandy, have long been celebrated for the number and perfection of specimens of this elegant type of cephalopodous shells. The first known English examples of this genus, as well as of Scaphites, were discovered by me in the chalk marl, at Hamsey, near Lewes, in Sussex, in 1810. Several very fine specimens of a large species (Turrilites tuberculatus), some of which are more than two feet in length, have been obtained from the same strata. The tubercles on the casts of this species are the bases of strong spines. The siphunculus, in the state of a pyritous cast, is preserved in some examples.

Figs. 13 to 27. These figures all refer to a very curious group of fossils, termed Nummulites, from the supposed resemblance of some of the flat disks to a piece of money. The complexity of their internal structure, and the supposed resemblance of their organization to that of the true Cephalopoda, led to many erroneous opinions as to the nature of the originals. That eminent physiologist, Dr. W. B. Carpenter, has recently investigated the intimate structure of the whole group, and the results are given in a beautiful and masterly memoir in the Quarterly Journal of the Geological Society of London.[57] Dr. Carpenter has clearly shown that these fossils belong to the Foraminifera, and not, as some eminent naturalists have supposed, to the Bryozoa, or "Moss-corals." As the family to which they belong comprises a numerous assemblage of minute organic remains, many of which are delineated in the next plate (Plate LXII.), the reader is referred to the "Supplementary Notes," for a general description of the Foraminifera, in which is given a restored figure of the supposed living animal of the Nummulite, from Dr. Carpenter's memoir.

Fig. 13. The usual appearance of the common species of Nummulite (Nummulina lævigata). From Egypt.

Fig. 14. A specimen rubbed down, and exposing the internal cellular structure.

Fig. 15. An example in which the outer investment is partly removed.

Fig. 16. A vertical section of the same.

Fig. 17. This fossil, of which fig. 18, is a vertical section (Nummulites obtusa, of Sowerby), appears to belong to a different genus; probably Orbitolites, or Marginopora. Tertiary strata.

Fig. 19. A vertical section of a Nummulite, showing a cavity in the centre, probably from decomposition.

Fig. 20. A section of another species of Nummulite (N. dispansa ? of Sowerby);[58] Tertiary strata, India.

Figs. 21 to 26, are various sections of a fossil Nummulite, of which fig. 37, represents the flat surface (Nummulites complanata, of Parkinson. This fossil belongs to the genus Discospira of Mr. Morris).[59]

Fig. 28. A species of Foraminifera (Fasciolites, of Parkinson; Alveolina elliptica, of D'Orbigny).

Fig. 29. A transverse section.

Figs. 30, & 31. Enlarged views of the same fossil. Fig. 31. A longitudinal section.

Figs. 1, & 2. Rotalia trochiliformis, of Lamarck. Tertiary.

Fig. 3. Rotalia Beccarii, of Linnæus. Tertiary.

Fig. 4. Cristellaria rotulata, Lamarck. Chalk.

Figs. 5, 6, 7. Lituola nautiloidea, Lamarck. Chalk.

Fig. 8. Spirolina depressa, Lamarck. This and the specimens to fig. 21 inclusive, are tertiary fossils.

Fig. 9. Spirolina cylindracea, Lamarck.

Fig. 10. Orthocerina clavulus.

Fig. 11. Biloculina ringens, Lamarck.

Figs. 12, & 13. Quinqueloculina cor anguinum, Lamarck.

Figs. 14, 15, & 16. Quinqueloculina.

Figs. 17, 18, 19. Triloculina trigonula, Lamarck.

Fig. 20. Quinqueloculina opposita, Lamarck.

Fig. 21. Peneroloplis opercularis.

Fig. 22. Adelosina, of D'Orbigny; a recent species.

Figs. 23, & 24. Gyrogonites. The fossils here figured on a magnified scale as microscopic shells of the same family as those above described, received the name of Gyrogonites, or twisted stones. They prove to be the seed-vessels of a species of the common fresh-water plant, the Chara. The fruit of this genus consists of minute nuclei, with an external calcareous covering, composed of five spirally twisted plates, which unite at the summit. These fossils occur by myriads in many of the fresh-water secondary and tertiary limestones, as well as in the calcareous deposits now in progress of formation in our lakes. In the lacustrine limestones of the Isle of Wight (at Binstead, White Cliff, &c.), beautiful specimens may be obtained.[60] Professor E. Forbes has discovered Gyrogonites in the Wealden strata of the Isle of Purbeck, associated with shells of the genera Planorbis, Physa, Paluolina, &c.

Fig. 25. Polystomella crispa, of Linnæus. From the tertiary strata of the Apennines.

Fig. 26. Cristellaria ?

Figs. 27, & 28. Rotalia Beccarii. Apennines.

Fig. 30. Cristellaria galea, of Lamarck. Apennines.

Fig. 29. Cast of a species of Area; a bivalve shell, from tertiary strata, Bordeaux.

Fig. 31. A curious pteropodous shell (Vaginella depressa), from tertiary strata, Basterot.

Fig. 32. This appears to be an imperfect specimen of a bivalve having a fibrous structure, like Pinna. It is probably a fragment of an Inoceramus.

Figs. 1, & 2, represent the structure of the hinge in both valves of a genus of bivalves of which numerous fossil species are met with in the secondary strata, and two or three species still exist in the Pacific Ocean. The genus is named Trigonia, from the form of the hinge, and the specific names below are those given by Mr. Parkinson.

Fig. 3. Trigonia clavellata, of Parkinson, from the Kimmeridge clay, Hartwell, Bucks.

Fig. 4. Trigonia costata, Oxford clay, Wilts.

Fig. 5. Trigonia excentrica; upper greensand, Blackdown. Like most of the shells from this locality, the Trigoniæ are transmuted into silex.

Fig. 6. Trigonia dædalea, Blackdown.

Fig. 7. —— spinosa, Blackdown.

Fig. 8. Enlarged view of the spines of the above.

Fig. 9. Trigonia alæformis, Blackdown.

Fig. 10. —— rudis, Blackdown.

Fig. 11. a bivalve shell of the genus Productus (P. antiquatus, of Sowerby?), from the Mountain limestone. See description of fig. 9, Plate LXVII.

Fig. 12. Cast of a species of Trigonia (T. clavellata), from the Portland rock. Many beds of this oolitic limestone are almost entirely made up of casts of Trigoniæ, and chiefly of this species.

Fig. 13. Trigonia sinuata, from Blackdown.

Figs. 14 to 18. "Different views of a species of Harpax."—Mr. Parkinson. (Plicatula spinosa). From the Lias, Gloucestershire.

Fig. 14. The inner surface of the flat valve.

Fig. 15. Inner surface of the convex valve.

Fig. 16. Magnified hinge teeth of the flat, and fig. 17, of the convex valve.

Fig. 18. Magnified view of the adpressed spines on the external surface of the shell.

Fig. 1. A perfect specimen of one valve, showing the character of the hinge of Cucullæa decussata, of Parkinson. London clay. Herne Bay.

Fig. 2. Interior view of Crassatella tumida, of Lamarck. Eocene strata, Paris.

Fig. 3. Cardium Hillanum, of Sowerby. A beautiful silicified bivalve from Blackdown.

Fig. 4. Nucula ovum, of Sowerby. A common bivalve, in the Lias, Yorkshire.

Fig. 5. Inner view of Cyrena deperdita, of Parkinson. Plastic clay, Woolwich.

Fig. 6. Lima gigantea, of Sowerby, from Lyme Regis. This is a young and small specimen of a large bivalve that occurs in great perfection in the Lias.

Fig. 7. Cardinia Listeri, of Sowerby. From the Lias, Gloucestershire.

Fig. 8. Cast of a bivalve; genus uncertain.

Figs. 9 to 12. These fossils are the Trigonellites of Mr. Parkinson; and have since been referred to a genus named Aptychus. Their true relations are very problematical. Though found in pairs, there is no hinge or natural connexion. Some naturalists suppose they may belong to the internal organization of Ammonites, because certain kinds have been found collocated with particular species of that genus of Cepholopoda. At present I do not think there is any satisfactory evidence as to their real nature. Species occur in the Kimmeridge clay, and other subdivisions of the Oolite formation.

Figs. 9, & 12. Trigonellites lata, of Mr. Parkinson.

Figs. 10, & 11. —— lamellosa.

Figs. 13, & 14. Corbida revoluta, of Sowerby. London clay, Highgate.

Fig. 16. An imperfect specimen of Lysianassa (Mya) literata, from the fullers' earth of the Oolite, Wiltshire.

Figs. 15, & 17. Cardita senilis, of Sowerby. From the Red crag of Suffolk.

Fig. 1. A single valve, viewed interiorly, of a fine shell (Panopæa Aldrovandi, of Faujas St. Fond) from the Pleistocene or Newer Tertiary strata, that form a chain of low hills near Palermo, in Sicily. The shells in these deposits comprise almost all the genera and species that now inhabit the Mediterranean. They occur in the most beautiful state, deprived only of their colour; and groups are often met with of extreme elegance. The cabinet of the Marquess of Northampton contains an extensive and unrivalled series of these fossils, collected during his Lordship's residence at Palermo.

Figs. 2, & 4. A boring bivalve (Fistulana or Lithodomus) from the Oolite, Bath.

Figs. 3, & 5. Valves of a small Oyster from the Crag of Essex.

Fig. 6. A group of Lithodomi in limestone from the Oolite, Bradford, Wilts.

Fig. 7. A detached specimen from the same, showing the enclosed bivalve.

Figs. 8, & 10. Fine but imperfect specimens of a species of Teredo (Teredina personata, of Lamarck), from the Plastic clay of Epernay, France.

Fig. 9. A snail-shell (Helix arbustorum) found associated, and evidently contemporaneous, with bones of Mammoth, and extinct species of Deer, and other mammalia. From Brentford, in a bed of light calcareous earth, twenty feet below the surface.

Fig. 11. "A concamerated Teredo."—Mr. Parkinson. I am unable to ascertain the nature of this fossil.

Fig. 12. A species of Fistulana, from France.

Fig. 13. External surface of Chama squamosa of Brander. London clay, Hordwell.

Figs. 14, & 15, are the anchylosed caudal vertebræ of the tails of fishes. From the London clay, Isle of Sheppey.

Fig. 16. "A small oyster with a spathose structure."—Mr. Parkinson. This shell is probably the flat valve of a species of Dianchora, of Sowerby; from the Chalk.

Fig. 1. A fossil Oyster (Ostrea Marshii, of Sowerby), from the Cornbrash of the Oolite, Wiltshire.

Fig. 2. The fossil Cockscomb Oyster, (Ostrea carinata, of Lamarck,) from the Lower chalk, Havre, France.

Fig. 3. The elegant fossil shell here figured is a peculiar and most abundant species in the Lias formation; specimens are not uncommon, in which every part of the shell is as perfect as if just thrown up on the sea-shore. It belongs to the genus Gryphites (Gryphea incurva, of Sowerby,) the shells of which are nearly related to the oysters, but are distinguished by the deep concave under-valve, and its curved beak, and the almost flat upper shell. The testaceous substance is of a finer laminated structure than in the Ostrea, and the hinge-ligament is inserted in an elongated curved groove.[61]