4o 



ZOOLOGICAL 



ORDER CROCODILIA (Crocodiles, &c ; 24 Species). 



CROCODILIDJE (Crocodiles ; 13 Species). Plate 20, Map iv. 

 Crocodiles have a fairly wide distribution, occurring in the greater part 

 of Africa, Madagascar, Southern Asia, the extreme north of Australia, the 

 Fiji Islands, and tropical America. Four species occur in the New World, 

 three in Africa, two in Madagascar, two in Australia, and the rest in the 

 Oriental Region and eastwards to the Fiji Islands. A small, short-nosed 

 species found in West Africa is made the type of a distinct genus 

 (Osteoleemus) ; all the rest are placed in the genus Crocodilus. 



ALLIGATOEID-ffi (Alligators and Caimans; 9 Species). 

 Plate 20, Map iv. 

 The members of this family have an interesting and peculiar distribu- 

 tion. Only two genera are known, excluding the doubtful Perosuchus. The 

 typical genus (Alligator) consists of three species, one of which occurs in the 

 South-eastern United States, another in the Yang-tse-Kiang, and a third 

 whose habitat is unknown. The Caimans {Caiman), distinguished by 

 having bony armour on the lower surface of the body, are five in number, 

 and are restricted to Central and South America. The presence of an 

 Alligator in the Yang-tse-Kiang, so far removed from its relatives, is very 

 remarkable, and it is still more curious that of the three species of the 

 genus it is the one most closely allied to the Caimans. 



GAVIALID-ffi (Gavials or Garials; 2 Species). Plate 20, Map iv. 



These peculiar long-snouted Crocodilians are placed in two separate 

 genera, Gavialis gangeticus being the well-known creature inhabiting the 

 large Indian rivers, and Tomistoma schlegelii the other species occurring in 

 the Malay Peninsula, Sumatra and Borneo. The Gavials, more properly 

 called Garials, feed almost entirely on fish, and consequently are harmless 

 to human beings. 



ORDER CHELONIA (Tortoises and Turtles ; 

 269 Species). 



TRIONYCHID^I (Soft Tortoises ; 30 Species). Plate 20, Map iv. 



This family is distinguished from other Chelonians by the fact that the 

 carapace is covered with soft leathery skin instead of hoi'ny shields, and the 

 feet provided with distinct digits and three claws. Half a dozen genera are 

 known, and their range of distribution includes the warmer parts of Asia, 

 Africa and North America. The typical genus Trionyx contains 20 species 

 which have a range as wide as that of the whole family. All the Soft 

 Tortoises are of aquatic habits, most of them inhabiting rivers and feeding 

 on fish, amphibians and molluscs. 



CARETTOCHELYDID^: (Fly River Turtle; 1 Species). 

 Plate 20, Map iv. 



This family contains only a single peculiar Turtle (Careilochelys 

 insculpta) which inhabits the Fly River, in New Guinea. Like the 

 Trionychidse. this species has the shell covered with soft leathery skin, but 

 its limbs are converted into paddles, and provided each with only two claws. 



CHELYDID-S: (Side-necked Tortoises; 31 Species). Plate 20, Map v. 



This family is one of two for which we have adopted a common popular 

 name. This bears allusion to the method of withdrawing the head by a 

 horizontal bending of the neck. From the Pelomedusidse, the other family 

 so characterised, the present group is distinguished by the fact that when 

 the head is withdrawn the neck still remains partly exposed. Nine genera 

 are distinguished, five of which are South American, and four confined to 

 Australia and New Guinea. The most remarkable species of the family is 

 the Matamata Tortoise (Chelys fimbriata), a native of Guiana and Northern 

 Brazil. Possessing a pointed and tube-like nose, a triangular head, and a 

 neck covered with peculiar fringed processes, with a deeply corrugated shell, 

 this Tortoise presents a most ungainly appearance. 



PELOMEDUSID-E (Side-necked Tortoises; 17 Species). 

 Plate 20, Map v. 



This family, the second of the side-necked group of Tortoises, is dis- 

 tinguished by the fact that the head and neck can be completely withdrawn 

 within the shell so as to be invisible. Only three genera are described, two 

 of which (Sternothserus and Pelomedusa) are confined to tropical and South 

 Africa and Madagascar, with eight and one species respectively. The third 

 genus, Podocnemis, contains six South American species and one, strangely 

 enough, confined to Madagascar. 



CHELONnXE (Turtles; 11 Species). Plate 20, Map v. 



Turtles are purely marine creatures, and in accordance with their 

 aquatic habit their limbs are modified into paddles for swimming purposes, 

 with one or two claws. Only two genera can be satisfactorily distinguished 

 in recent forms, Chelone with two species, and Thalassochelys with nine. 

 The well-known Green Turtle (Chelone mydas) furnishes the turtle soup so 

 prized in banquets. This species has a wide distribution in tropical and 

 subtropical seas, the principal collecting grounds for commercial purposes 

 being off the island of Ascension, the West Indies, and the Mosquito Coast 

 in Nicaragua. The second species of Chelone (C. imbricata) is an equally 

 useful creature. It is known as the "Hawksbill Turtle," and is the source 

 of the valuable "tortoise-shell" of commerce. Co-extensive in range with 



the Green Turtle, it differs from the latter in the fact that the horny shields 

 covering the shell overlap like the tiles of a house-roof instead of meeting at 

 their edges. Of the genus Thalassochelys, the best-known species is the^ so- 

 called Loggerhead Turtle (T. caretta), a huge creature with a shell averaging 

 3| feet in length. 



TESTUDINID^ (Land-Tortoises and Terrapins; 156 Species). 

 Plate 20, Map v. 



This is the typical, and at the same time much the largest, family of 

 Chelonians, containing considerably more than half the known species 

 The species are found in all the zoogeographical regions except the 

 Australian. Twenty-seven genera are recognised at the present day, Testudo 

 being the principal one with over 50 species. These occur in all parts of the 

 area covered by the family, while two species are well-known inhabitants of 

 Southern Europe. In the Galapagos Islands, Mauritius, and neighbouring 

 islands occur a number of giant forms which are probably the survivors of a 

 once more extensive group. The Terrapins of the genus Chrysemys are a 

 purely American group, as are also Malacoclemmys (with seven species) and 

 the Box-Tortoises (Cistudo), of which four species are recognised. The 

 Hinged-Tortoises (Cinixys, four species) and those of the genus Homo-pus 

 (six species) are confined to- Africa. The European Pond-Tortoise (Emus 

 orbicularis) is interesting as being the species which ranges farthest north. 

 In Europe it has occurred about as far north as St Petersburg. 



PLATYSTERNID^ (The Big headed Tortoise ; 1 Species). 

 Plate 20, Map vi. 



This family includes only a remarkable-looking creature, known as the 

 Big - headed Tortoise (Platysternum megacephalum), inhabiting chiefly 

 Burma, Siam, Southern China, and the Philippine Islands. It is, however 

 so rare, that little or nothing is recorded of its habits. Besides its huo-e 

 head, this curious Tortoise possesses an unusually flat shell and a tail of more 

 than ordinary length. 



CINOSTERNID-E (Mud-Terrapins; 14 Species). Plate 20, Map vi. 



The Cinosternidse. are entirely confined to the New World, half the species 

 occurring in the United States, five in Central America, and two in the 

 northern part of South America. They are small creatures, never exceeding 

 about 6 inches in length, inhabiting swamps and marshes, and feeding on 

 small fishes, worms, and insects. In most of the species the lower portion 

 of the shell is hinged in two places, so that the animal can retreat within 

 and close the " box " both in front and behind. 



DERMATEMYDID^ (Mud-Terrapins; 4 Species). Plate 20, Map vi. 



The three genera constituting this family are closely related to the 

 previous group of Mud-Terrapins, but have a much more restricted range, 

 being, in fact, confined to a comparatively small area in Central America. 

 The best-known species is Dermaiemys mawi, sometimes known as Maw's 

 Terrapin. 



CHELYDRIDJu (Snappers and Alligator-Terrapins; 3 Species). 

 Plate 20, Map vi. 



This again is an entirely New World family, ranging from Canada to 

 Ecuador. Only two genera are recognised, the typical one Chelydra con- 

 taining two species known as Alligator-Terrapins. Their popular name is 

 said to be due, not to their habits, but to a supposed resemblance to an 

 alligator provided with a shell. The better-known species has a curious 

 distribution, since it occurs in the rivers of North America as far south as 

 Mexico and also in a detached area in Ecuador. This peculiar gap in 

 distribution appears to be partially filled by the second species, which occurs 

 in Mexico and Guatemala. The second genus (Macroclemmys) contains a 

 single species known as Temminck's Snapper (M. temminckii), a native of 

 North America from Western Texas to Florida, and ranging northwards to 

 Missouri. All the members of this family have ferocious and even dangerous 

 habits, snapping viciously at anything within their reach, and sometimes 

 inflicting severe wounds on human beings. 



SPHARGIDiE (The Leathery Turtle; 1 Species). Plate 20, Map vi. 



The Leathery Turtle or Luth (Sphargis or Dermochelys coriacea) is the 

 sole representative of its family, and by far the largest of all living 

 Chelonians, full-grown specimens attaining a length of over 6 feet. This 

 important creature has a wide distribution, occurring in all tropical seas and 

 occasionally straying to more temperate waters. The main distinguishing 

 features of the family are firstly, the vertebra? and ribs are not fused with the 

 carapace or shell, as in all other Chelonians ; secondly, the shell is covered 

 with leathery skin ; and thirdly, the limbs are modified into paddles and are 

 without claws. 



Sub-Class PROSAURIA (1 Species). 



HATTERIID^ (The Tuatera; 1 Species). Plate 20, Map vi. 



This family is formed for the reception of a Lizard-like creature which is 

 confined to the small islands in the Bay of Plenty, New Zealand. Formerly 

 the creature was common on the main islands, but it has rapidly diminished 

 in numbers and is now apparently extinct except in the few small islands 

 indicated. It is, perhaps, the most interesting animal in the whole of the 

 New Zealand fauna, being the only living representative of a group which 

 reached its zenith in Permian and Triassic times. In the words of Gadow, 

 the Prosauri, the group in question, " seem to represent the central stem of 

 the reptilian tree." 



