pe === Se + eure pee gh ye at eth erete Natural History Museum Library 300009433 o “h BRITISH MUSEUM (NATURAL HISTORY). DAYS AND HOURS OF ADMISSION. The Exhibition Galleries are open to the Public, free, every day of the week, except Sunday, in January and February, | from 10 a.m, till 4 p.m. Sa: March and April, . ees eee | - May to August, Spt ty ay See as ’ Phe, of September and October, SS Loomer a November and December, eS ee ee = ae Also, from May Ist to July 15th, on Mondays and Sehinigglene till’ 8 p.w., one ats and from July 15th to August ee on Mondo and senate - only, till 7 P.M. is : .e Museum is closed on Good-Friday, Christmas-Day, and on days of Public Fast or Thanksgiving. W. H. FLOWER. Director. | |: | : : ii | EST ERTES PP PAI ot taint hata hee AABN ALAN SN RAAN j | REPTILES AND FISHES IN THE DEPARTMENT OF ZOOLOGY. OF THE BRITISH MUSEUM (NATURAL HISTORY). —< SPSOSSSSSSSSSSSSSSCSSOSSOSSOSSOs ILLUSTRATED BY 101 WOODCUTS AND 1 PLAN, POSS SSSSSSSSSSSSSSSSSSSOSSSe PRINTED BY ORDER OF THE TRUSTEES. 1887. CITTITtt 000000090 0,9 9 *- 5, ‘ — = ica ri ae i a pert ‘ ‘ ne : ; — Ls 1 i sits aes Se < a. i oS 4 rag e Ry a Fs 3 S 4) a at a P 7 Lat eee ee + i ri a s* * < ont Teh ToT y - i Np a aa Py ee Oe" Rene eae 2 oe . ho Le wiki Say Rates ae i4 Sp tv eal wii atts Spa Ce OS, AS a P LT ae ae : ? - | d . 7 = ? 5 a 4 , siete, * a) ; HA es ees » >, eee 3 rot . 7 ~~ a 2 ; tal eae ieee: : eR Ba ee od ipa tlt That obo ad Ne ete yy i + a en aan 2 ite onivenltcania) ig Ca ee Med : , Me heen ere ee Sg. fT 15 ial 1) > * . - ‘ = La Z ‘0 THE REPTILE GALLE RY, GENERAL NOTES ON REPTILES. THERE is but a short step from the Class of Birds to that of Reptiles. No doubt, as regards external appearance, the dissimi- larity between the living animals of these two classes is sufficiently great to allow of a sharp line of demarcation being drawn between them: Birds being shortly characterized as warm-blooded vertebrate animals clothed with feathers, Reptiles as cold-blooded, and covered with horny or bony shields, tubercles, or “scales.” But there - are numerous and important agreements between these two classes, especially in the structure of their skeleton, in their internal organs, and their mode of propagation; and their close relation- ship becomes still more apparent when fossil forms are examined, such as Hesperornis and Archeopteryx, of which a cast is placed in Case A, in the corridor leading from the Bird- into the Reptile- Gallery (see also the figure given on p. 35 of the Geological Guide). Reptiles are termed “ cold-blooded” because the temperature of their blood is raised but a few degrees above, and varies with, that of the outer atmosphere, owing to the imperfect separation of the divisions of their heart, which allows more or less of a mixture of the arterial and venous currents of the blood. Reptiles are ovi- parous or ovoviviparous; no important change takes place after exclusion from the egg; they breathe by lungs throughout life. Their skull articulates with the vertebral column by a single occi- pital condyle (see fig. 1), and their lower jaw with the skull by a separate bone (quadrate) (see figs. 1, 13, and 14). The remains of the oldest known Reptiles, those found in the Permian formations, seem to belong to the Rhynchocephalian type, B2 2 REPTILE GALLERY. Back view of skull of Crocodile. 0, single occipital condyle; g, quadrate bone. of which only one representative is still living (in New Zealand). Reptiles flourished and attained their greatest development in the Secondary period—Pterosaurians (large flying Lizards, see Geolo- gical Guide, p. 39), Dinosaurians (huge terrestrial Reptiles far exceeding in size our largest Crocodiles), Dicynodonts, Ichthyosau- rians, and Plesiosaurians (large marine creatures, Geological Guide, pp. 41, 45, 47), Crocodiles, Lizards, and Turtles lived in abun- dance ; Snakes, however, did not appear before the Tertiary period. At present some 4000 species of Reptiles are known, which are unequally divided among five Orders, viz. Crocodilia (Crocodiles and Alligators), Rhynchocephalia, Lacertilia (Iazards), Ophidia (Snakes), and Chelonia (Tortoises and Turtles). In this classification of Reptiles the naturalist is guided much more by the structure of the skeleton and the other internal organs than by the external appearance. In fact, in Reptiles, as in many other classes of the Animal Kingdom, outward similarity is decep- tive as to the natural relationship—that is, as to the degree in which they are related to each other as descendants from a more or Jess remote common ancestor. Take, for instance, a Crocodile, a Lizard, a Slowworm, and a Snake. The observer who, like the CROCODILES. 3 naturalists of the last and preceding centuries, is guided by external appearance only, would without hesitation place the Crocodile and Lizard together, and associate the Slowworm with the Snake ; whilst a study of their internal structure shows the Lizard and the Slowworm to be most closely related to each other, and both nearer to the Snake than to the Crocodile. Reptiles are most abundant in hot climates, become less nume- rous in higher latitudes, and are altogether absent in the Arctic and Antarctic regions. In the Gallery— Wall-Cases 1-10 contain the Crocodilians. i. a 5 Rhynchocephalians. 2 11-22 +f Lizards. ay 23-27 3 Snakes. AS 28-44, He Tortoises and Turtles. Large specimens are exhibited separately on stands placed on the floor of the Gallery. Order I. CROCODILIA. The Crocodilians differ in many anatomical characters from the Lacertilians, or true Lizards, with which they were formerly associated on account of their external resemblance. The organs of their chest and abdomen are separated from each other by a muscular diaphragm; their heart is divided into four cavities, as in the higher vertebrates. The ribs are provided with two heads for the articulation with the vertebra, and with processes directed backwards; and their abdomen is protected by a series of transverse bones, as may be seen in the skeleton of the large Cro- codile (Case EH, opposite Wall-Case 5). The teeth are implanted in sockets, while in other recent Reptiles they are united to the jaws. The tongue is completely adherent to the floor of the mouth. The nostrils are situated close together at the upper side of the extre- mity of the snout; the eyes and the ears likewise are near to the upper profile of the head, so that the animal can breathe, see, and hear whilst its body is immersed in the water, the upper part of the head only being raised above the surface. When it dives, the nostrils are closed by valves, a transparent membrane is drawn over [Cases 1-10. } 4 REPTILE GALLERY. the eye, and the ear, which is a horizontal slit, is shut up by a movable projecting flap of the skin. The limbs are weak, the ante- rior provided with five, the posterior with four digits, of which three only are armed with claws, and which are united together by a more or less developed web. The tail is long, compressed, crested above, very powerful, and admirably adapted for propelling the body through the water. The back, tail, and belly are protected by a dermal armour formed of quadrangular shields, of which the dorsal and, in several Alligators, also the ventral contain true bone imbedded in the skin. The Crocodilians are thoroughly aquatic in their habits, and the most formidable of all the carnivorous freshwater animals. Crocodiles and Alligators, when young, and the Gharials through- out their existence, feed chiefly on fish; but large Crocodiles attack every animal which they can overpower, and which they drown before devouring. The eggs, of which one (of Crocodilus porosus) is exhibited in Case 2, are oblong, hard-shelled, and deposited in holes on the banks of rivers and ponds. The flesh of these animals is not eaten, but their hides have lately been introduced as an article of commerce; a portion of the skin pre- pared for the trade may be seen in Case 5. The large stuffed Crocodilians are arranged in two groups in the middle of the Gallery, that (C) nearest the entrance containing the Old-World forms, the other (D) the American kinds. The smaller specimens occupy Wall-Cases 1-9, and a series of skulls is exhibited in Case 10. About 25 species are known. Crocodiles proper (Crocodilus) are distinguished from the Alli- gators by having the fourth lower tooth passing into a notch at the lateral edge of the upper jaw. They inhabit Africa, Southern Asia, the tropical parts of Australia, Central America, and the West Indies. The Indian Crocodile (Crocodilus porosus) grows to a length of 80 feet, and is very common in the East Indies and Tropical Australia. A large specimen obtained in North-east Australia is exhibited in the middle of the Gallery. The African — Crocodile (Crocodilus vulgaris) attains nearly to the same size as the Indian species. It was worshipped by the ancient Egyptians, and was once common in Egypt proper. It has now been almost exter- TUATERA. 5 minated in the lower parts of the Nile, but infests in great numbers all the freshwaters of Tropical Africa; and it is believed that more people are killed by Crocodiles than by any other of the wild beasts of Africa. The Gharials (Gavialis) may be readily recognized by their extremely long and slender snout. The Gharial of the Ganges (G. gangeticus), of which a large specimen (B) is mounted in the middle of the Gallery opposite to the entrance, is abundant in that _ river and its tributaries, and attains to a length of 20 feet. It feeds chiefly on fishes, for the capture of which its long and slender snout and sharp teeth are well adapted. Old males have a large cartilaginous hump on the extremity of the snout containing a small cavity for the retention of air, by which means these indi- viduals are enabled to remain under water for a longer time than females or young. . In the Alligators (Alligator) the fourth lower tooth is received in a pit in the upper jaw, when the mouth is shut. With the exception of one species which has been lately discovered in China, they are found only in America. They do not grow to the large size of the true Crocodiles. The species most generally known is A. mississippiensis, which abounds in the southern parts of North America. The Black Alligator (A. sclerops) iscommon in South America as far south as 32° lat. S. Order II. RHYNCHOCEPHALIA. Of this Order, which seems in the Permian and subsequent forma- tions to have been represented by various genera, one species only has survived to our period. It is the Tuatera of the Maoris, or Hatteria of naturalists. Case 11 contains an example of this inter- esting Reptile, with skeleton and skulls. It is the largest of the few Reptiles inhabiting New Zealand, but scarcely attains toa length of 2 feet. Formerly it was probably found in several parts of the northern island ; but at present it is restricted to afew small islands in the Bay of Plenty, where it lives in holes feeding on other small animals. Externally there is nothing to distinguish the Tuatera from ordinary Lizards; but important differences obtain in the structure of its skeleton, viz. the presence of a double [ Cases 7-9. | [Case 11.}j [Cases 1-22.] 6 REPTILE GALLERY. horizontal bar across the temporal region, the firm connection of the quadrate bone with the skull and pterygoid bones, biconcave vertebre (as in Geckos and many fossil Crocodilians), the presence of an abdominal sternum and of uncinate processes to the ribs (as in Birds). Order III. LACERTILIA, or Lizarps. The Order of Lizards comprises over 1600 species, which exhibit a great variety of form and structure. Some, like our common Lizards, possess four legs and a long tail, and are endowed with great rapidity of motion ; others, like the Chame- leons, are arboreal, and have their limbs and tail adapted for climb- ing on the branches of trees ; others, like the Geckos, can ascend smooth vertical surfaces, their toes being provided with special adhesive organs. The limbs may be rudimentary or disappear entirely, as in our common Slowworm, in which case the Lizard assumes the appearance of a Snake; but, in all, rudiments at least of both pectoral and pelvic bones are hidden under the skin. Lizards may be characterized as Reptiles with the skin covered with scales Fig. 2. e @ d c b “e0enscgceeee ERO ASN ONCE Hind iegs of Lizards, to show the gradual abortion. a, Chaleides ocellatus; b, Chalcides mionecton; c, Chalcides tridactylus ; d, Lygosoma lineo-punctulatum ; e, Chalcides guentheri. —— LIZARDS. < or tubercles ; with non-expansible mouth, the rami of the mandible being firmly united anteriorly by a suture; with four or two limbs, or at least rudiments of pectoral and pelvic bones; with teeth which are ankylosed to the jaws, and not implanted in sockets; with a transverse anal opening. Moveable eyelids and an ear-opening are usually present. If the limbs are developed, they are generally provided with five digits armed with claws; but as in some kinds the limbs get weaker and shorter, the number of toes is gradually reduced ; and there are Lizards in which the little limb terminates in a single useless toe, or is even entirely toeless. The tongue offers very remarkable differences in form and function. It is simple, broad, short, soft in the Geckos, Agamas, and Iguanas, and is pro- bably an organ of taste; in the majority of the other families it is narrow, more or less elongate, often covered with scale-like papille, and with a more or less deep incision in front, assuming more and more the function of an organ of touch. It is of extraordinary length, worm-like, and terminating in two fine, long points in the Monitors, in which, as in Snakes, it acts as a feeler only. The tongue of the Chameleons will be noticed subsequently. Lizards are spread over the whole world except the very cold regions, and are, like all other Reptiles, most numerous, both as regards species and individuals, between the tropics. They are divided into many families, some of which can be alluded to here by name only :— Families—1l. Geckonide. 2. Eublepharide. 3. Uroplatide. 4. Pygopodide. 5. Agamide. 6. Iquanide. 7. Xenosauride. 8. Zonuride. 9. Anguide. 10. Anniellide. 11. Helodermatide. 12. Varanide. 18. Xantusiide. 14. Tetide. 15. Amphis- benide. 16. Lacertide. 17. Gerrhosauride. 18. Sceincide. 19. Anclytropide. 20. Dibamde. The last family, the Chameleontide, is so distinct from all the others that some herpetologists would remove it from the Lacertilia altogether. The majority of Lizards, especially the smaller kinds, are not suitable objects for exhibition in a dry state; they must be pre- served in spirit; consequently only a selected series is exhibited in this Gallery. 8 REPTILE GALLERY. [Case 1l.} The Geckonide, or Geckos, are Lizards of small size, the largest measuring about a foot, and have always attracted attention by their possessing the faculty of ascending smooth surfaces, or even of running on the ceilings of rooms like a fly. For this purpose the Head of Gecko verticillatus (Kast Indies). lower surface of their toes is provided with a series of moveable plates or disks, by the aid of which they adhere to the surface over which they pass. Geckos are found in almost every part of the globe between and near the tropics, frequenting houses, rocks, and trees. Fic, 4, Rs eS! Boe ass e See SS ziitees GY 9, 2s a eee “eens ee Sone REO oe, © 7 @ oe NY a Hind leg of Gecko verticillatus. With few exceptions they are nocturnal, and consequently large- eyed, animals, the pupil being generally contracted in a vertical direction. Geckos are extremely useful in destroying insects, and, though greatly feared by those not acquainted with their habits, are perfectly harmless. Nearly all Geckos possess a voice; and the —S—— ee on LIZARDS. 9 large Gecko verticillatus, which is extremely common in the East- Indian Archipelago, utters a shrill cry, sounding like “tokee” or tock.” The Varanide, or Water Lizards, are the largest of Lizards, some exceeding a length of six feet. A few (Varanus griseus, Case 11) are terrestrial, but the majority semi-aquatic, the former having a rounded, the latter a compressed tail, with a sharp saw- like upper edge, which assists them greatly in swimming, and at the same time constitutes a formidable weapon with which these powerful animals can inflict deep wounds on the incautious captor. They range all over Africa, the Indian region, and Australia. Their prey consists of other vertebrate animals—small mammals, birds, frogs, fishes, and eggs. In India they are well known under the misnomer “ Iguanas” as dangerous neighbours to poultry-yards. Among the species which grow to the largest size may be men- tioned the gigantic Monitor (Varanus giganteus, Case 16), from N. Australia; the two-streaked Monitor (V. salvator, Cases 15-17), common in the East-Indian Archipelago; the common Indian Water-Lizard (V. bengulensis); and the African Monitor (V. niloticus), ranging over the whole of Tropical Africa (Case 14). The Helodermatide contain a single genus, the remarkable Heloderma horridum, an inhabitant of the western parts of Mexico. As far as is known at present, it is the only Lizard whose bite is poisonous. Its teeth are fang-hke, provided with a deep groove as in some Snakes, and the submaxillary gland is enormously developed and secretes the poisonous fluid. It is about two feet long. The Tejide (bottom of Case 18) are the American represen- tatives of the Lizards proper, from which they somewhat differ in their dentition. The Teguexins (Tupinambis teguexim and nigro- punctatus) are the largest, attaining to a length of about four feet, and found in most parts of the South-American continent. The Dracena guianensis is a rare Lizard, found in the Guianas and Brazil, and was considered a kind of Crocodile by old authors, who saw a distinct resemblance to those animals in its compressed, keeled tail, as well as in the large tubercles which are arranged pretty regularly on its back. [ Cases ee [Case 18. ] [Case 18. ] Of the Amphisbenide, singular worm-like Reptiles, a few [Case 18.] [Case 18, ] [Case 18. ] [Case 18. ] 10 REPTILE GALLERY. specimens and a skeleton are exhibited. All their external cha- racters testify to their mode of life; they are burrowing animals, passing the whole of their existence under ground in loose soil, sand, or ant-heaps. The skin is not protected by either scales or scutes, but divided by circular and longitudinal folds into quad- rangular segments arranged in rings. The colour of the skin is either whitish, reddish, or greyish, without any ornamentation. Legs are absent (with the exception of the genus Chirotes, in which a pair of very short fore legs are developed). The head and tail are both short; and the superficial similarity of the two extremities in some of the species has led to the belief that they could progress backwards and forwards with equal facility. Their eyes are quite rudimentary, hidden below the skin; ear-openings are likewise absent. The Amphisbenians are inhabitants of hot countries— Africa, America, and the countries round the Mediterranean. About 50 different species are known. Lizards proper (Lacertide) are confined to the Old World, and found in Europe, Asia, and Africa. They seldom reach a length of eighteen inches (Lacerta ocellata), and feed on small animals only, insects and worms being the principal diet of most kinds of Lizards. The Common British Lizard is Lacerta vivipara; the Sand Lizard (ZL. agilis) and Green Lizard (L. viridis) bemg more locally distributed in the Southern Counties and the Channel Islands, but very abundant in various parts of the continent of Europe. The Anguide include limbed as well as limbless forms; of the latter the Slowworm or Blindworm (Anguis fragilis), common in Great Britain, is the best known. The Glass Snake, or Sheito- pusik (Pseudopus pallasii), common in South-eastern Europe and Western Asia, is another example. The Scincide or Skinks, recognizable by their round imbricate scales, also include forms in which the limbs are rudimentary or absent. The largest forms of this family are Australian, as Tiliqgua gigas and nigrolutea, and Trachydosaurus, the last remarkable for their rough scales and short tail, somewhat re- sembling the cone of a fir-tree. A very curiously shaped form, also from Australia, is Hyernia stokesit, with its short conical tail armed with dagger-pointed spinous scales. ) LIZARDS. iE The Iguanide are American pleurodont Lizards (see Fig. 7) exhi- biting an astonishing variety of form. The largest and best known are the Iguanas (Iguana rhinolophus and tuberculata, Case 20), found Iguana tuberculata (Brazil). in the forest-regions of Tropical America only, in the neighbourhood of water, into which when frightened they jump from the overhang- ing branches of trees, to escape capture by swimming and diving. Feeding exclusively on leaves or fruits, they are themselves highly esteemed as food, and their eggs also are eagerly sought for by the natives. Iguanas grow to a length of five feet. The marine Iguana (Amblyrhynchus cristatus, Case 19) is an inhabitant of the Galapagos Islands, living on the rocks of the shore and feeding on seaweeds. No other Lizard enters sea-water. Among the smaller representatives of this large family may be mentioned the Anolis, extremely numerous in Tropical America and the West Indies— small, slender, agile, thoroughly terrestrial and arboreal Lizards, Californian “ Toad” (Phrynosoma cornutum),. [Cases 19-21.) | Case 22,] 12 REPTILE GALLERY. of rare beauty and variety of colour, and forming a striking contrast to the species of Phrynosoma (Case 19) of North America and Mexico, which, on account of their shape and sluggish habits, have earned the name of Horned or Californian Toads (fig. 6). The Agamide represent the Iguanas in the Old World. They are distinguished by the acrodont dentition, the teeth being anky- Lower jaws, showing the acrodont (a) and pleurodont (6) dentition. losed to the upper edge of the jaws, an arrangement which occurs also in the Rhynchocephalians, some Amphisbenians, and the Chameleons. Lizards of this family are most abundant in the Indian and Australian regions, showing a great variation of form | analogous to that of the preceding family. The perhaps most highly specialized Agamoid is the genus Draco, small winged Lizards from the East Indies (fig. 8). The Dragons are tree-lizards, and possess a peculiar additional apparatus for locomotion: the much- prolonged five or six hind ribs are connected by a broad expansive fold of the skin, the whole forming a subsemicircular wing on each side of the body, by which they are enabled to take long flying leaps from branch to branch, and which are laid backwards at the sides of the animal while it is sitting or merely running. The Frilled Lizard (Chlamydosaurus kingii) is an Australian Agamoid, growing to a length of two feet. It is provided with a frill-like fold of the skin round the neck, which, when erected, f Fig. 8. MIN) ci xin Dragon (Draco teniopterus) ; Siam. 13 14 REPTILE GALLERY. resembles a broad collar, not unlike the gigantic lace-ruffs of Queen Elizabeth’s time. When startled, this Lizard is said to rise with Frilled Lizard from Australia (Chlamydosaurus kingit). the fore legs off the ground, and to jump in kangaroo-fashion. An extraordinary creature is the Moloch (Moloch horridus), also from Moloch horridus (Australia). Australia; the tubercles and spines, with which it is entirely covered, give it a most repulsive appearance ; but it is perfectly harmless. Other Lizards of this family are the Australian Amphi- bolurus and the African and Asiatic Uromastix. LIZARDS. 15 The Chameleontide, or Chameleons, are almost peculiar to [Case 22.] Africa, and most numerous in Madagascar; one (the common) species extends into India and Ceylon. No other member of the Order of Lizards shows such a degree of specialization as the Chameleon. The tongue, eyes, limbs, tail, skin, lungs are modi- Fig. 11. Common Chameleon. fied in a most extraordinary manner to serve special functions in the peculiar economy of these animals. They lead an exclusively arboreal life: each of their feet is converted into a grasping hand, Fig. 12. Hand of Chameleon. by means of which, assisted by a long prehensile tail, they hold so fast to a branch on which they are sitting that they can be dis- lodged only with difficulty. Their movements are slow and awk- ward on the ground, and still more so in the water, where they c [Cases 23-27. | 16 REPTILE GALLERY. are nearly helpless. The tongue is exceedingly long, worm-like, with a club-shaped viscous end ; they shoot it out with incredible rapidity towards insects, which remain attached to it, and are thus caught. ‘The eyes are almost entirely covered by a thick lid, pierced with a small central hole, and not only can be moved in any direc- tion, but each has an action independent of the other—one eye may be looking forwards, whilst an object behind the animal is examined with the other. The faculty of changing colour, which they have in common with many other Lizards, is partly dependent on the degree in which the lungs are filled with air, and different layers of chromatophores* are pressed towards the outer surface of the skin. The adult males of some of the species possess long horns or other excrescences on the head. The largest species attain a length of 18 and 20 inches. Order IV. OPHIDIA, or Snakes. The Snakes, or Ophidians, are scaly Reptiles, with exceedingly elongate, limbless body, without sternum, without, or with only rudiments of, a pelvis, with the mandibles united in front by an elastic ligament. The ribs are articulated movably with the verte- bral column. The jaws are armed with sharp, fang-like teeth, which are ankylosed to the bone. The peculiar mobility of the jaw-bones enables these animals to extend the gape in an extra- ordinary degree, and to work their prey (which generally is much thicker than the Snake itself and always swallowed whole) through the throat into the stomach. The tongue is narrow, retractile into a basal sheath, and terminates in two long thread-like points ; it is frequently and rapidly exserted when the animal is excited or wants to touch an object. Snakes have no eyelids; but the part of the epidermis which covers the eye is transparent, convex, and has the shape of a watch-glass, behind which the eye moves. There is no ear-opening. ‘The scales are not isolated formations, as in fishes, but merely folds of the outer skin, which is cast off in a single piece several times every year. The head is generally covered with large, symmetrical, juxtaposed plates (see figs. 15 & 16), and the * Cells in the skin in which the colouring-pigment is deposited. SNAKES. 17 belly with large transverse shields. The organs of locomotion for the exceedingly elongate body of the Snakes are the ribs, the number of which is very great, nearly corresponding to that of the vertebre of the trunk. Although the motions of Snakes are in general very quick, and may be adapted to every variation of ground over which they move, yet all the varieties of their locomo- tion are founded on the following simple process. When a part of their body has found some projection of the ground which affords it a point of support, the ribs, alternately of one and the other side, are drawn more closely together, thereby producing alternate bends of the body on the corresponding side. The hinder portion of the body being drawn after, some part of it finds another support on the rough ground or a projection, and the anterior bends being stretched in a straight line, the front part of the body is propelled in consequence. During this peculiar kind of loco- motion, the numerous broad shields of the belly are of great advantage, as, by means of the free edges of those shields, they are enabled to catch the smallest projections on the ground, which may be used as points of support. Snakes are not able to move over a perfectly smooth surface. Non-venomous Snakes have generally two rows of short, thin Skull of Snake (Python). m, maxillary ; pm, premaxillary ; g, quadrate bone. teeth, pointed like a needle, on each side of the upper jaw, and one in the lower; sometimes one or two of the anterior teeth are c2 18 REPTILE GALLERY. longer than the rest, but they are not grooved or perforated, nor do they communicate with a poison-gland. The poisonous Snakes are armed with a long canaliculated tooth in front of the upper jaw; the channel terminates in a small slit at the extremity, and is in connection with a duct which carries Fig. 14. Skull of Poisonous Snake (Vipera nasicornis). m, maxillary, with poison-fang; a bristle is inserted in the openings of the channel at the base and point of the tooth; d, undeveloped poison- fangs; pm, premaxillary ; g, quadrate bone. the poisonous fluid from a large gland to the tooth. This venom- gland is situated on the side of the head, above the angle of the mouth, and invested by a dense fibrous sheath, which is covered by a layer of muscular fibres. At the moment the Snake opens its mouth to bite, the muscles compress the gland, and force its contents through the excretory duct into the channel of the venom- tooth, whence it is ejected into the wound. The force with which the gland is compressed is shown by the fact that irritated animals have been seen to spout the poison from the aperture of the tooth to a considerable distance. The venom-apparatus serves these creatures not only for defence, but also, and chiefly, for the pur- pose of overpowering their prey, which is always killed before they commence to swallow it. The dental apparatus is not the same in all poisonous Snakes. The venom-tooth is always fixed to the maxillary bone; but in some this bone is as long, or nearly as long, asin the non-venomous Snakes, and generally bears one or more ordinary teeth on its hinder portion. This venom-tooth is always more or less erect, SNAKES. 19 not very long, and its channel generally visible as an external groove. Poisonous Snakes with such a dentition resemble also in other respects the non-venomous Serpents, and are designated as Venomous Colubrine Snakes. In the other venomous Snakes the maxillary bone is extremely short, and does not bear any ordinary teeth, only an exceedingly long curved fang, perforated in its entire length. Although this tooth also is fixed to the bone, the bone itself is very mobile; so that the tooth, which is laid backwards when at rest, can be erected the moment the animal prepares to strike. The tooth is occasionally lost ; but others, in different stages of development, lie in the gum behind it, ready to take the place of the lost tooth. Most Snakes feed on living animals, a few only on eggs. They are oviparous or ovoviviparous. They number about 1800 species, and are spread over all temperate regions, but are most numerous between the tropics. They are absent in New Zealand. The Order is divided into three Suborders and numerous minor groups. Suborder I. OpHtp11 CoLUBRIFORMEs. (Innocuous Snakes.) Typhlopide (Burrowing or Blind Snakes); Stenostomatide, Tortricide, Xenopeltide, Uropeltide, Calamariide, Oligodontide, Colubride, Homalopside (Freshwater Snakes); Psammophide (Sand-Snakes) ; Dendrophide (Tree-Snakes) ; Dryiophide, Dipsa- dide, Scytalide, Lycodontide, Amblycephalide, Pythonide, Boide, Erycide, Acrochordide. Suborder II. Opu1p11 CoLUBRIFORMES VENENOSI. (Venomous Colubrine Snakes.) Cobras and Coral Snakes (E/apide) and Sea-Snakes (Hydro- phide). Suborder III. Oruip11 Virerirormgs. (Viperine Snakes.) Vipers (Viperide), Pit-Vipers, and Rattlesnakes (Crotalide). Snakes are most unsuitable objects for preservation im a dry state, as no method is known by which the singularly regular [Case 26.] [Case 26. | 20 REPTILE GALLERY. arrangement of their scales, and their sometimes beautiful colo- ration and lustre can be preserved. Therefore only a small propor- tion of the collection is exhibited, of which the following deserve particular notice :— The Burrowing or Blind Snakes (Typhlopide &c.) are small worm-like species, with teeth in one of the jaws only, and without enlarged ventral plates. They are numerous in Africa and India, though occurring also in tropical America and Australia; one species is found in South-eastern Europe. The Colubride form the great bulk of the Order, and are found in every part of the temperate and tropical regions, but are only scantily represented in Australia and the islands of the Fig. 15. Smooth Snake (Coronella levis). natrix). Pacific. To this group belong the Smooth Snake (Coronella levis), found in the southern parts of England, and the Common or Ringed Snake (Tropidonotus natrix). Spilotes and Ptyas are known by the name of Rat-Snakes. The Freshwater Snakes (Homalopside) are thoroughly aquatic, several of them even entering the sea. In some points of their organization they approach the truly marine Hydrophide. They feed on fish, and belong chiefly to the Indian region. The Tree- or Whip-Snakes (Dendrophide and Dryophide) are exceedingly slender and elongate, and some are exquisitely SNAKES. 21 coloured, green being the predominant hue. They feed chiefly on tree-lizards and birds, and are found in all the tropical regions. Bucephalus capensis is from South Africa. The Pythonide, or Rock Snakes, are found in the hottest parts of Africa, Asia, and Australia, and attain a very large size (from 8 to 24 feet). They climb as well as swim, most of them preferring the neighbourhood of water. Like the Boas, to which they are closely related, and from which they differ chiefly in the presence of intermaxillary teeth, they overpower their prey by constriction. The Pythons of Africa and Asia and the Morelia of Australia represent this family. The Boidea, or Boas, are restricted to the tropical parts of Fig. 17. Anaconda, from Tropical America (Boa murina). [ Cases 24, 25.] [ Cases 23, 24.] | Case 26. ] [Case 27. ] [Case 27.] 22 REPTILE GALLERY. the New World. The Anaconda (Boa murina), of which a spe- cimen (F) measuring 29 feet is exhibited in a separate glass case, and represented in the act of seizing a Peccary (which frequently falls a prey to this species), is the largest Snake known, the true Boa constrictor being a much smaller species (Case 24). The Erycide (Case 23) are small Snakes, closely allied to the Boas, but differing by possessing a very short nonprehensile tail ; their habits are terrestrial, or even burrowing. Cliftia fusca and Erebophis asper, the latter from New Britain, belong to this family. The Acrochordide are distinguished by their small, wart-lke, not imbricate, tubercular or spiny scales. Acrochordus javanicus, from Java and the Malayan peninsula, grows to a length of 8 feet. The Elapide are poisonous Snakes, with the physiognomy of the harmless Colubrine Snakes: they occur in all the tropical regions, and are most abundant in species in Australia, where they form almost the entire Snake-fauna. The Indian Cobra (Naya tripudians) and the African Cobra (Naja haje) ave two of the best known and most dreaded Ophidians. They possess the re- markable faculty of expanding their neck when irritated, by raising the elongated ribs of this region, and thus stretching the skin outwards on each side; the dilatable portion is frequently orna- mented on the back by a figure resembling a pair of spectacles. The Hamadryad, Ophiophagus elaps, is allied to the Cobra, but attains to a much larger size, and is one of the most dangerous venomous Snakes, as it is well known to frequently attack people. It feeds on other Snakes, and occurs in many parts of the Indian continent and archipelago. A specimen, 13 feet long, is exhibited in a spirit-tank opposite the wall-case. The true Elaps, or Coral- Snakes, are small, brilliantly-coloured Snakes, and their very small mouth renders them much less dangerous to man. The Sea-Snakes, Hydrophide, are inhabitants of the tropical parts of the Indian and Pacific Oceans, and most abundant in the East-Indian archipelago and in the seas between Southern China and North Australia. They pass their whole life in the sea. Their tail, which is compressed and paddle-shaped, answers all the pur- poses of the same organ in a fish, and their motions in the water are almost as rapid as they are uncertain and awkward on land, SNAKES. 23 These Snakes are highly poisonous; their dentition resembling that of the preceding family. Their food consists entirely of fish. Sea-Snake (Hydrophis), from the Indian Ocean. The greatest size to which some species attain is about 12 feet. Pelamys bicolor and Hydrophis are examples of this family. The Vipers (Viperide) and Rattlesnakes (Crotalide) are Snakes [Case 27. | with the most perfect poison-apparatus ; the latter family being distinguished from the former by the presence of a deep pit on the side of the snout, between the eye and the nostril. These Snakes have generally a short thick body and a broad head, are [ Cases 28-44. ] 24, REPTILE GALLERY. slow in their movements, and nocturnal; some live on bushes, most of them on the ground. They are viviparous. The true Vipers are chiefly African, a few species only occurring in Europe and Asia. The common British Viper is one of the smallest of BEE a <= Loy IK) Oa us Common Viper (Vipera berus). this group; the Puff-Adder (Clotho arietans), the most dangerous Snake of South Africa. The Pit-Vipers and Rattlesnakes are found only in Asia and America, most abundant and reaching a larger size in the latter part of the world. The true Rattlesnakes (Crotalus) are distin- guished by the “rattle” at the end of the tail, formed by several horny rings, which the animal shakes when irritated, producing a peculiar sound. It is stated that the length of the “ rattle” indicates the age of the individual; and it is a fact that rattles of such a length and so many joints (twenty-one), as are exhibited in Case 27, are now of extremely rare occurrence, as these dangerous creatures, with the advance of cultivation, have now but rarely the chance of surviving to a very old age. Order V. CHELONIA (Tortoises and Turrss). The Chelonians, or Tortoises and Turtles, are distinguished from all other Reptiles by the more or less ossified case or “ shell” which encloses the body, and into which most of the species can TORTOISES AND TURTLES. 25 retract their head and limbs. This armour consists of two shields united by their lateral margins; the upper, or carapace, is formed by the expansion and union of the vertebre and ribs; the lower, or plastron, by dermal bones only. In most of these animals the carapace presents three series of central bony plates—the vertebral medially,and the costal laterally —and they are surrounded bya series Fig. 20. Skeleton of Tortoise, in a vertical section through the carapace. e, neck; v, dorsal vertebre ; ¢, tail; 7, costal plates ; pl, plastron; s, shoulder-bones ; p, pelvis. of marginal plates; the plastron bones are generally nine in number, one median and four pairs. Horny epidermic plates cover the carapace and plastron; their arrangement is also symmetrical, but by no means corresponds to that of the underlying bones; they constitute what is called the “ Tortoise-shell,” which in some species has great commercial value. The jaws are toothless, covered by a horny bill, rarely hidden under fleshy lips. The four limbs are always well developed, and modified according to the mode of life of the species,—the terrestrial Tortoises having short, club-shaped feet furnished with blunt claws; the freshwater Turtles, digits distinct, armed with sharp claws, and united by a more or less developed membrane or web; and, finally, the marine 26 REPTILE GALLERY. Turtles, having their limbs transformed into regular paddles, re- sembling those of Cetaceans. The tail is constantly present, but frequently extremely short ; in a few forms only it attains to a con- siderable length. Chelonians are oviparous, and the eggs are generally covered with a hard shell. The Chelonians form only a small part of the Class Reptilia, the number of species amounting to about 300. If they occupy in this Gallery almost half of the wall-cases, it is because they are more suited than the other Reptiles for being preserved and exhi- bited in a dried state. Chelonians are divided into the following Suborders :— . Sphargide, or Leather-Turtles. . Cheloniide, or Sea-Turtles. . Trionychide, or Freshwater Turtles. . Emydide and Chelydida, or Freshwater Tortoises. 5. Testudinide, or Land Tortoises. rm CO OO = In the first three several important characters remind us of other orders of Reptiles, especially Crocodilians, whilst the two last are farthest removed from the ordinary Reptilian type. [Case29,] 1. The Sphargide are a geologically ancient type, im which the formation of a protecting bony carapace has made but little advance. The skin, which in a fresh state is flexible, like thick leather, contains bony deposits arranged like mosaic; but this dermal shield is not united to the vertebre and ribs, which remain free, and are not particularly dilated, as may be seen in the large skeleton (G) exhibited opposite to Case 29. In this arrangement the dermal shield and skeleton are in the same relation to each other as in the Crocodiles. The structure of the limbs is the same as in the marine Turtles, with which the Leather-Turtle agrees in its mode of life; the bones of the paddles, however, are still more simple, merely rods, and claws are entirely absent. Only one species exists in our time (Sphargis coriaceus), which seems to become gradually rarer, although it is found occasionally through- out all the seas of the tropical and temperate regions, specimens having strayed now and then to the British coast. This Turtle is, perhaps, the largest living Chelonian, exceeding a length of 6 feet, and is said to be herbivorous. TORTOISES AND TURTLES. - 27 2. Cheloniide or Marine Turtles. Their feet are transformed into long compressed fins, the anterior pair considerably longer than the posterior, the digits bemg enclosed in a common skin, out of which only one or two claws project; the carapace is broad and much depressed, but large interspaces between the extremities of the ribs remain unossified; it is covered with symmetrical horny plates. These Turtles are thoroughly marine animals, their fin-like feet and their light shell rendermg them the best swimmers in the class of Reptiles. They sometimes live hundreds of miles distant from the shore, to which, however, they periodically return in order to deposit from 100 to 250 soft- shelled eggs, which are buricd in the sand. The food of some species (Chelone) consists exclusively of alge; others (Caretta, Caouana) subsist upon fish and mollusca. They are found in all the intertropical seas, but sometimes they travel far into the tem- perate regions, specimens being occasionally captured on the British coasts. The flesh and eggs of all the species are edible, the Green Turtle (Chelone viridis) being the most esteemed. The Hawk’s-bill Turtle (Caretta imbricata) furnishes the commercial tortoise-shell ; the finest sort comes from Celebes, whence it is exported to China. Specimens of polished shell from the Indian Ocean and Jamaica are exhibited. A common Atlantic species is the Loggerhead Turtle (Caouana caretta), which forms an exception to all other recent Chelonians in having five instead of four epidermic plates on the side (costals). 3. Trionychide, Freshwater Turtles, with much depressed shell, which is covered with soft skin, and not with epidermic plates ; the digits are movable, strongly webbed, and each foot has only three sharp claws, belonging to the three inner digits, exactly as in Crocodiles. The jaws are covered with fleshy lips, and the snout is produced in a short tube bearing the nasal orifices, and enabling the animal to breathe while the rest of the head is submerged under water. These animals are thoroughly aquatic and carni- vorous, and inhabit the hotter parts of Asia, Africa, and North America. We may note the Javanese and Gangetic Trionyx (Trionyx javanicus and gangeticus), and the Nilotic Trionyx (7. niloticus, T. africanus), as showing the largest size attained by these Turtles. [ Cases 8, 29.] [Cases 29, 30. | [ Cases 31-38. | [Cases 39-44, ] 28 REPTILE GALLERY. 4. The Emydide, or Freshwater Tortoises, possess a perfectly ossified carapace covered with epidermoid plates, and movable digits furnished with sharp claws. The mode of life of some is aquatic, of others almost terrestrial; the former having their shell least convex, and a more or less developed web between the toes. Thoroughly aquatic are the Alligator Terrapens of North America (Chelydra, Case 33), in which the tail attains to a great length, and is furnished with a crest resembling that of a Crocodile ; Che- lydra temminckiwt is the largest freshwater Tortoise. The East- Indian Batagur (Case 34) approach in their physiognomy and habits and in size the Freshwater Turtles. The smaller forms are most abundant in North America, and sometimes beautifully marked (Emys picta, rivulata, ornata, &c., Case 36). The Euro- pean species (Lutremys europea, Case 38) is abundant in South Europe, and found, less frequently and locally, in Germany as far north as Berlin; its fossil remains have been found in the fen- country. Pya«idea, Geoemyda, Lutremys live as much on land as in water; and, finally, we have an example of an exclusively ter- restrial Emydoid in the Box-Tortoise ( Cistudo carolina, Case 88), which lives in the woods of the southern parts of the United States, and possesses, like other Freshwater Tortoises, a hinge in the lower shield, rendering its anterior portion movable. A lid is thus formed by which the posterior opening of the shell can be com- pletely closed. The following Freshwater Tortoises differ from the preceding in not being able to retract the head and neck, but in bending it side- ways under the shell, as the American Podocnemys expansa (Case 31), of which a fine skeleton is exhibited, and the Australian Chelodina. But the most remarkable form of this group is the Mata-Mata Tortoise (Chelys fimbriata, Case 31), a native of Brazil and the Guianas. Its head and neck are fringed with warty appen- dages, floating in the water like some vegetable growth, whilst the rough, bossed carapace resembles a stone,—an appearance which evidently is of as great use to this creature in escaping the obser- vation of its enemies as in alluring to it unsuspicious animals on which it feeds. 5. Testudinide, or Land Tortoises, with very convex carapace, and with feet adapted for progression on land only. They are TORTOISES AND TURTLES. 29 The Mata-Mata (Chelys fimbriata) ; British Guiana. vegetable-feeders, and inhabit the hotter parts of the Old as well as New World, but are absent in Australia. The greater part are referable to the genus Testudo, of which one species occurs in Southern Europe (Testudo greca, Case 42) ; another closely allied species is 7. mauritanica, extremely abundant in Morocco and Algiers, and imported in great numbers into England. But the most interesting forms of this group are the Gigantic Tortoises (Cases 39-41), which were formerly found in great numbers in the Mascarene and Galapagos islands. At the time of their dis- covery these islands were uninhabited by man or any large mammal; the Tortoises therefore enjoyed perfect security, and this, as well as their extraordinary degree of longevity, accounts for their enormous size and the multitude of their numbers. They could be captured in any number with the greatest ease within a few days, and proved to be a most welcome addition to the stock of provisions. They could be carried in the hold of a ship, with- out food, for months, and were slaughtered as occasion required, each Tortoise yielding, according to size, from 80 to 300 pounds of excellent and wholesome meat. Under these circumstances, the numbers of these helpless creatures decreased so rapidly, that in the beginning of this century their extermination was accomplished in the Mascarenes; and now only a few remain in a wild state in Aldabra and some of the islands of the Galapagos group. We may note particularly the gigantic Land Tortoise of Aldabra (Tes- tudo elephantina) ; the large male specimen (H) exhibited weighed 870 pounds, and although known to have been more than 80 years 30 REPTILE GALLERY. old, was still growing at the time of its death; the gigantic Land Tortoise of Abingdon Island (7. abingdonii), remarkable for its Fig, 22. Testudo abingdonit. The Tortoise of Abingdon Isl., Galapagos. long neck and its thin shell, which may be easily pierced by a knife. The specimens exhibited were obtained by Commander W. E. Cookson during the visit of H.M.S. ‘ Petrel’ to the Galapagos Islands in 1875, and were probably the last survivors of their race. Pak, FISH GALEERY BATRACHIANS. (Frogs anp Newrs.) GENERAL NOTES. A TABLE-case placed in the corridor which leads from the Bird- to the Fish-Gallery contains a small series of this class of animals. The softness of their skin prevents their being preserved in a dry condition ; therefore of the thousand species known only a few typical specimens are exhibited. Although Batrachia are popularly regarded as Reptiles, their zoological affinities are with the Fishes, from which it is by no means easy to separate them. They may be defined as cold-blooded * Vertebrata, the majority of which have a pair of lungs which lie below the digestive tract, which for some, or the whole, period of their existence breathe by gills, have three chambers to the heart, and two or no occipital condyles ; their limbs, if present, have not more than five fingers developed, and if, as is rare, they possess dorsal fins, these are merely folds of the integuments without those supporting carti- laginous rays which are found in Fishes. The skin is soft, moist, richly provided with blood; small scales with rounded edges are found only in some of the Limbless forms. In the majority of Batrachians the young when it leaves the egg is totally unlike, and afterwards gradually changes into, the form and condition of the perfect animal. This change is called ‘ meta- morphosis.” The young or larva is fish-like and breathes by gills, * See page 1 with regard to this term. 32 FISH GALLERY. which are gradually exchanged for lungs; in some Batrachians in which the larva is a vegetable-feeder, the change from a vege- table to an animal diet is accompanied by a shortening of the intestine; and in many the loss of a tail is compensated by the growth of four limbs, whilst in others the tail is persistent through- out life. The metamorphosis is very complete in Frogs and Toads, in which the limbless, long-tailed larva or ‘Tadpole’ differs so much from the perfect animal that only direct observation can afford the proof of these changes being the developmental stages of the same creature. However,a few Tailed Batrachians (Proteide, Sirenide) retain the gills throughout their existence, though pro- ducing one or two pairs of limbs; and a certain number of Frogs belonging to various genera (Rana, Hylodes, Rhinoderma, Pipa, &c.) are known to leave the egg in the perfect form. The greater number of Batrachians are oviparous ; some, like the Salamander, are ovoviviparous. The eggs are deposited in water or damp places, and generally (in all the British species) enveloped in a gelatinous mass, which protects them from mecha- nical injury and atmospberic influences: those of the Frogs form large coherent lumps, whilst the Toads deposit theirs in long strings, and the Newts attach theirs singly to water-plants. In a few species the female carries the eggs in a pouch on her back (Nototrema), or in dorsal cells (Pipa), or attached to her belly (some Rhacophori) ; in a few the male carries the eggs round his legs (Alytes) or in a gular sac (Rhinoderma). The tongue is occasionally absent ; when present it is generally attached to the front end of the floor of the mouth instead of, as in the higher Vertebrates, at the hinder end; in the majority of the Tailless Batrachians it can be thrust out of the mouth, and act as the organ with which they seize their prey. (See fig. 25, p. 37.) In many species a sac or a pair of sacs are developed on the throat or the side of the head in the males; they act as resonants to the waves of sound set up by the air which is passing from the lungs, and the species that possess them are much more noisy than those that are without them. All Batrachians have numerous small glands imbedded in their skin for the secretion of a whitish slimy fluid. In some these glands TAILLESS BATRACHIANS. 33 are more developed than in others, and when many are placed close together they form protuberant masses, sometimes on each side of the neck (parotoids of Toads and Salamanders), sometimes on the loin or on the hind legs, or on other parts of the body. There is no doubt that in some species this secretion has more or less poisonous properties ; that of the Common Toad is sufficiently dis- agreeable to dogs, birds of prey, &c. to act as a protection to the Batrachian ; but that of some South-American species (Bufo agua, Dendrobates) is said to be a much more active poison, and to be used by the Indians as one of the ingredients of their arrow- poison. All the Batrachians which flourished in the older formations, Carboniferous to Trias inclusively, belonged to the extinct order Stegocephala or Labyrinthodonta, and were succeeded in the Cre- taceous by the Tailed, in the Tertiary by the Tailless Batrachians, which order appears to have now attained its highest point of development. No fossil Ceecilian has as yet been found. Recent Batrachians are referable to three orders, viz. :— 1. Ecaudata, Tailless Batrachians, such as Frogs and Toads ; 2. Caudata, Tailed Batrachians, such as Salamanders, Newts, and Permanent Gill-breathers ; 3. Apoda, Limbless Batrachians or Ceecilians. Order I. ECAUDATA, or TAILLESS BATRACHIANS. This order, which comprises over 800 species, includes Batra- chians destitute of a tail, with shortened body and four limbs, of which the hinder pair is longest and adapted for leaping. Their skeleton shows many peculiarities. The following account refers to the Frog :—The skull is large and flattened, with enormous orbits; the vertebral column shortened, with constantly eight pree- sacral and one sacral vertebra, and a coccygeal style formed by the ossification of the caudal notochord of the early stage of life. The following is an enumeration of the principal bones of the skull :—On the upper surface two large bones, the fronto-parietals (fig. 23, fp), formed by the fusion of the frontals and parietals, leaving uncovered anteriorly a portion of the ethmoid (e); a pair of nasals (n) ; the prootic (po) on each side between the fronto- D2 834 FISH GALLERY. parietals and the squamosal (sq); the latter is a mallet-shaped bone, the basal extremity of which is in contact with a small bone, the quadrato-jugal (qj), which represents the quadrate and jugal Skeleton of Rana esculenta. of higher Vertebrates; there are then two premaxille (pm) and two mawille (mx), bearing, in certain species, closely-set, small, acute teeth. On the lower surface we distinguish the vomers (vo), each of which bears sometimes a group of teeth, the palatines (pl), horizental, rod-shaped bones, the ethmoid (e), a large T-shaped TAILLESS BATRACHIANS. 30 parasphenoid (psp), and the pterygoids (pt). On the back of the skull are the exoccipitals (eo), with a condyle on either side of the foramen magnum for articulation with the first vertebra ; there is no basioccipital. The toothless lower jaw is composed of several bones, as in the Reptiles, to which is added on each side a peculiar symphyseal (sy). The number of presacral vertebre (v) is eight ; the ninth, or sacral (sv), gives attachment to the pelvis. The vertebrze possess strong transverse processes but no ribs, and, save in the first and sacral, the centra are proccelous or concavo-convex. The coccyx (c) is a long styliform bone, articulating with the sacral vertebra by a double concavity receiving the double condyles of the latter. The pectoral arch (fig. 23) is composed of a pair of precoracoids (peo) and a pair of coracoids (co) nearly parallel, and firmly con- nected in the median line by a narrow cartilage, the epicoracoid (eco) ; this structure of the pectoral arch is termed the “ Firmi- sternal,” to distinguish it from the “ Arciferous ” type as seen in many families—for instance the Toads, in which the coracoid and Sternal apparatus of Leptodactylus pentadactylus. precoracoid on the one side are connected by an arched epicoracoid cartilage overlapping that of the other side (fig. 24). In front is the omosternum (ost), composed of a cartilaginous disk and a bony 36 FISH GALLERY. style ; posteriorly the sternum (sé), similarly formed. Above the scapula (sc), on the dorsal side, is the suprascapula (ssc), partly cartilaginous. The fore limbs present this peculiarity, that the ulna and radius (cr) coalesce into a single bone; the functional digits number four, but there is a rudimentary thumb (po). The pelvic arch also differs much from that of higher Vertebrates ; the alza (7/) are elongated bones set parallel to the vertebral column, and join- ing posteriorly the pubis and ischium (pt), which are united into a single small discoid bone. The acetabulum, or socket for the reception of the head of the femur, is far removed from the sacrum. In the hind limb also the tibia and fibula (tf) are united into a single bone, and the two proximal elements of the tarsus (a; astra- galus, ca) are so elongated and strong as to resemble the real tibia and fibula of other animals—the Newts, for instance. The toes are also much elongated, and number five, with-an additional ossicle (VI) on the inner side, which is regarded as a rudimentary sixth toe. The Tailless Batrachians are distributed over the whole surface of the globe except the Arctic Regions, and are most abundant in the tropical and subtropical zones. They are divided into two sub- orders and fifteen families as follows :— Suborder PHanEroctossa, furnished with a tongue, and with the internal ear-openings separated. Series A. Firmisternia*. Families :—1]. Ranide. 2. Dendrobatide. 38. Engystomatide. 4. Dyscophide. 5. Ceratubatrachide. i Series B. Arcifera*. Families :—6. Cystignathide. 7. Dendrophryniscide. 8. Bufo- nde. 9. Hylide. 10. Pelobatide. 11. Discoglosside. 12. Am- plignathodontide. 13. Hemiphractide. Suborder Il. Acrossa, without tongue, and with a single internal ear-opening. Families :—14, Dactylethride. 15. Pipide. * For the meaning of this term see p. 35. TAILLESS BATRACHIANS, Oo” The Ranide, or true Frogs, have teeth in the upper jaw; the transverse processes of the sacral vertebra are not distinctly dilated. Two species occur in this country: the common Frog (Rana tem- Fig. 25, ~ WAS ~ Liana temporaria (Common Brown frog). poraria) is indigenous; the second species, the Edible Frog of the Continent (R. esculenta), has been introduced, and has thoroughly established itself in some parts of Norfolk. The Bull-Frogs, so called from their bellowing powerful voice, are R. catesbiana of North America, and R. tigrina, the largest and commonest Frog of India; R. adspersa, also one of the largest species, is found in various parts of tropical Africa, and remarkable for its toad-like appearance. ‘This family also contains arboreal types, of which Rhacophorus maximus, from the Himalayas and the hills of Assam, is a representative. In this genus the webs between the fingers and toes are much developed and very broad, so that some natu- ralists have represented this structure to be of service to the frog in taking flying leaps (the Flying Frog of Wallace), What is - 38 FISH GALLERY. certain is that the disk-like dilatations of the tips of the fingers act as adhesive organs (fig. 26), by means of which the animal attaches itself to vertical or smooth surfaces, as may be observed in the common Tree-Frog from the continent, which is frequently kept in captivity in this country. Fig. 26. Foot of Hylambates palmatus. The Deéndrobatide are small Tree-Frogs, closely allied to the preceding family, but destitute of teeth, in which respect they resemble the Toads. The savage tribes of some parts of South America extract a deadly poison for their arrows from Dendrobates tinctorius, of which a specimen is exhibited, and from other allied species. The Cystignathide represent the Ranide in tropical America and Australia. They differ from the true Frogs in the structure of the sternal apparatus, which, as in Toads, belongs to the “ Arciferous”’ type. Several of the genera lack altogether a web between the toes (Leptodactylus), whereas others (e. g. Pseudis) have the toes extensively webbed. This Pseudis Frog was believed by the earliest observers who studied the fauna of the Guianas to reverse the course of the ordinary metamorphosis and to change into a fish. This fable originated in the enormous size of the tadpole, which frequently far exceeds that of the perfect animal. Several larvze of this interesting Batrachian are exhibited. The Ceratophrys, or Horned Frogs, also belong to this family. The Bufonide, or true Toads, have no teeth, and the transverse processes of the sacral vertebra are more or less strongly dilated or mallet-shaped. Two species, Bufo vulgaris (the Common Toad) and Bufo calamita (the Natterjack), represent this group in the TAILLESS BATRACHIANS. 39 Fig. 27, Cerutophrys ornata (Horned Frog). British Isles. The largest species is the Agua Toad (Bufo marinus) of Sonth America, which attains to a length of 8 inches, the limbs not included, and which possesses enormous parotoid glands. The Hylide, or true Tree-Frogs, resemble very closely the arboreal Ranide as regards form and habits; but the structure of their skeleton proves their affinity to the Toads, from which they are distinguished by the presence of teeth in the upper jaw. The large Tree-Frog exhibited, Hyla dolichepsis, from New Guinea, and the common European species, Hyla arborea, are examples. Closely allied to Hyla is Nototrema (fig. 28), a marsupial Frog provided with a dorsal pouch, into which the ova are introduced (probably by the male) immediately after they are laid, and preserved from injury until hatched. The commonest species, N. marsupiatum, is a native of the Andes of Ecuador. The species of Phyllo- medusa, or ‘“quadrumanous”’ Frogs, are still more strongly adapted to arboreal life, the first digit of both hands and feet being opposable to the others, like the thumb of the band. Several species are known from tropical America. 40 FISH GALLERY. Xenopus levis, from Tropical Africa. TAILLESS BATRACHIANS. 41 The Discoglosside differ from all the preceding families in pos- sessing short ossified rudimentary ribs, and the vertebree, instead of being proccelous are opisthoccelous, two characters in which they approach the Newts. They are represented by but few species; among them the Fire-bellied Toad (Bombinator igneus), so abundant in many parts of Germany, and the curious “ Midwife Toad ” (Alytes obstetricans), an inhabitant of Western Europe: the latter owes its name to the assistance rendered by the male to his mate during the deposition of the ova; he then twists the strings of ova round his legs and carries them until they reach maturity. The Amphignathodontide and Hemiphractide, as well as the Ce- ratobatrachide of the series Firmisternia, are remarkable for pos- sessing teeth in the lower as well as in the upper jaw. Pipa amerneaa (Surinam Toad). AY FISH GALLERY. The Dactylethride (Xenopus, fig. 29) of tropical Africa and the Pipide of South America are small groups which form the suborder of tongueless Frogs—the former being chiefly distinguished by the presence of teeth in the upper jaw, whereas the latter are absolutely toothless. The Surinam Toad (Pipa americana, fig. 30) is well known for its curious mode of reproduction, the eggs being placed by the male in cells on the back of the female, where they remain until the completion of the metamorphosis. Order Il. CAUDATA, orn TAILED BATRACHIANS. Elongate, lizard- or eel-like in form, with two, or, exceptionally, one pair of limbs and with a tail. Short ribs are constantly present, and the vertebral centra are biconcave or proccelous. Over 100 species are known, from Europe, Temperate Asia, North Africa, and North and Central America, but they are entirely absent in the Southern Hemisphere. They are arranged in four families :— 1. Salamandride. 2. Amphiumide. 3. Proteide. 4. Si- renide@. Amblystoma tigrinum (Axolotl of Mexico). The Salamandride, or Newts and Salamanders, lose their gills before they reach the adult state. However, there are instances occurring in various genera, of which the Axolotl (fig. 31) is the a a, TAILED BATRACHIANS. 43 best known, of specimens retaining the gills throughout life, whereas other individuals of the same species undergo the regular meta- morphosis. The common land-Salamander (Salamandra maculosa) is very common over nearly the whole of Europe and in North Africa. Three species of Newts (Mole) are found in Great Britain, viz. the large Crested Newt (M. cristata), the Common Smooth Newt (M. vulgaris, fig. 32), and the Palmated Newt (M. palmata). These Molge vulgaris (Common Smooth Newt). species live in the water in spring and during part of the summer, whilst they are engaged in depositing their eges, coming at in- tervals to the surface for the purpose of respiration. The remainder of the year they pass on land. The Amphiumide are exclusively aquatic, although they lose the gills during metamorphosis. They are easily distinguished from the Salamandrid@ by the absence of eyelids. The species of Amphiuma (fig. 33) are eel-like creatures, with very small limbs, from North AA, FISH GALLERY. America. The Gigantic Salamander (Megalobatrachus maximus), from Japan and China, belongs to this family; it is the largest living Batrachian, attaining a length of four feet, and the living Fig. 33. Amphiuma means, from North America. representative of the fossil Salamander of CEningen, the remains of which were originally regarded as those of man (Homo diluvii testis). The Proteide and Sirenide are permanent gill-breathers, and TAILED BATRACHIANS. 45 distinguished from the preceding families by the absence of maxillary bones. Proteus anguinus (fig. 34) inhabits the sub- terranean waters of the caves of Carniola, and in consequence of its long sojourn in absolute darkness its eyes have become rudimentary aud are concealed in the skin, which is entirely devoid of pigment. Fig. 35. Fig. 34. Froteus anguinus, from the caves of Carniola. Fig. 35. Siren lacertina, from North America. Siren (S. lacertina, fig. 35), a native of North America, possesses only one pair of limbs, viz. the anterior. 46 FISH GALLERY. Order IIT. APODA, or LIMBLESS BATRACHIANS. Fig. 36. Ureotyphlus africanus. These are worm-like burrowing crea- tures, destitute of limbs, without or with only a rudimentary tail, frequently with small scales imbedded in the skin; the vertebree are biconcave. About 35 species are known, belonging to one family, Cecilude, which is found in tropical Africa, the East Indies, and tropical America. A specimen of Siphonops annulatus, the com- monest species in South America, and a skeleton of Ichthyophis glutinosus, from the East Indies, are exhibited. The species figured (fig. 36) has been recently dis- covered in West Africa. Very little is known of their habits; they seem to live buried in mud or very soft moist soil. The ova are of large size and few in number. Some species are ovoviviparous. Ichthyo- phis deposits its eggs, shortly after impreg- nation, in a hole in damp earth. These eggs form a small mass, which the mother protects by coiling herself round it. In the embryo large external gills are developed within the egg ; and the larva is provided with an opening, or spiraculum, on each side of the neck. FISHES. A7 FISHES. Visitors who desire to inspect the exhibited series of Fishes have to pass from the Bird-Gallery on the ground-floor by the first corridor on the right-hand side into a large side Gallery, as shown on the plan accompanying this Guide. The contents are chiefly stuffed specimens * and skeletons; the former arranged in a continuous series in the Wall-cases numbered 1-44, the latter in Table-cases marked A-G. Large objects are exhibited in special cases, or placed on stands on the floor of the Gallery. GENERAL NOTES. The class of Fishes, of which now some 10,000 species are known, exhibits a much greater amount of variation of external form, and of diversity of their principal internal organs, than any of the higher Vertebrates. But as all, without exception, live in the water throughout life, they possess common distinctive characters in those systems of their organization which are in direct relation to their aquatic mode of life, viz. in the organs of respiration and locomotion. Fishes, therefore, may be described as vertebrate animals living in water, and breathing the air dissolved in the water by means of gills or branchize ; whose heart consists of two chambers only, viz. a single ventricle and single atrium; whose limbs, if present, are modified into fins, supplemented by unpaired, median fins; and whose skin is either naked or covered with scales or osseous scutes or bucklers. With few exceptions, Fishes are oviparous. * The collection of Fishes preserved in spirit is placed with other similar preparations in a separate locality, such specimens being preserved to meet the requirements of the scientific student, and generally unsuitable for exhibition. E 48 FISH GALLERY. The earliest fossil remains referred to this class are found in the Lower Silurian, in the form of small horny bodies which have been regarded as teeth of Cyclostomes or Lampreys. But the first undeniable evidence of a Fish, probably a Plagiostome, occurs in the Upper Silurian ; from the Devonian to the Cretaceous, Ganoids were extremely abundant and exhibited an endless variety of forms, many of which recall, with regard to external appearance, the Teleosteans of the present time ; from the former formation started also Chondropterygians and other Paleichthyes ; in the Tertiary Epoch the Teleosteans almost entirely replaced the Ganoids, and have continued to be the predominant type of Fishes down to our times. Fishes are distributed over all the waters of the globe, and may, on the whole, be divided into Freshwater and Marine forms. However, a sharp line cannot be drawn between these two kinds of Fishes, for there are not only species which can gradually accom- modate themselves to a sojourn in either salt or fresh water, but there are also such as seem to be quite indifferent to a rapid change from one to the other, as, for instance, Sticklebacks and some species of Clupea, or Herrings. Further, Fishes belonging to freshwater genera descend rivers and sojourn in the sea for a more or less limited period; whilst others annually or periodically ascend rivers for the purpose of spawning—for instance, the Salmon and many Sturgeons. Marine Fishes fall, with regard to their life and distribution, imto three divisions:—1l. Shore Fishes, that is, Fishes which inhabit chiefly parts of the sea in the immediate neighbourhood of land or banks ; 2. Pelagic Fishes, which inhabit the surface and uppermost strata of the open ocean, and approach the shores only accidentally or occasionally (in search of prey), or periodically (for the purpose of spawning); 3. Deep-sea Fishes, which inhabit such depths of the ocean as to be but little or not at all influenced by light or the surface temperature, and which, by their organization, are prevented from reaching the surface stratum in a healthy condition. But it must not be imagined that these three divisions are more sharply defined than Freshwater and Marine Fishes, and, like these latter, they gradually pass into each other. A number of Skeletons are exhibited in the wall-cases and table- 49 FISHES. "YoIIg Jo woyopeyg ee