1001 



CHELONIA. 



CHELONIA. 



1003 



E. terpentina. It lives in lakes and rivers, feeding on fish, and, aa it 

 would seem, on young birds. This is Teitudo serpentina, Linn. ; 

 C/ielydra terpentina, Schweigg., and Chelonura aerpentina, Say, &e. 



Emytanra atrpentina. 



Staurolyimt, Wagler. Head sub-quadrangular, pyramidal, covered 

 in front with a single very delicate scale only ; jaws more or less 

 hooked ; barbies under the chin ; twenty-three limbar scales ; sternum 

 thick, cruciform, moveable in front, furnished with eight or eleven 

 scales ; axillary and inguinal scales contiguous, placed on the sterno- 

 coatal sutures ; anterior feet with five nails ; posterior feet with four 

 only. 



6'. triporcatut ; S. odoratut, so called from the musky odour which 

 it is said to exhale. 



A'iimgternnn, Wagler. Head sub-quadrangular, pyramidal ; a single 

 rhomboidal plate upon the cranium ; jaws slightly hooked ; barbies 

 under the chin ; scales of the shell slightly imbricated ; limbar plates 

 to the number of twenty-three ; sternum oral, moveable before and 

 behind on a fixed piece, furnished with eleven scales ; alae short, 

 narrow, sub-horizontal ; a very large axillary plate and an inguinal 

 still larger ; tail long (in the males), unguiculate. 



K. icorpioides. It lives in marshes and on river-banks. K. Penntylva- 

 nicum lives in muddy waters, feeding on small aquatic animals, and 

 exhaling a strong musky odour. K. hirtijii *. 



Sub-Family 2. Pleurodere Elodians. 



The Pleuroderes, as their name indicates, have all of them the neck 

 retractile upon one of the sides of the anterior aperture of the cara- 

 pace ; but they are never able completely to draw it in between their 

 fore feet and under the middle of the buckler and plastron, like the 

 Cryptoderes. 



Ptltoctplialut, Dum. and Bibr. Head large, sub-quadrangular, 

 pyramidal, covered with large, thick, slightly imbricated plates ; 

 jaws extremely strong, hooked, without dentilations ; eyes lateral ; 

 plates of the carapace slightly imbricated ; no nuchal plate ; feet 

 slightly palmated : two large rounded scales at the heels ; nails 

 straight, robust ; tail unguiculate. 



P. Tracaxa. 



Podocnemii, Wagler. Head slightly depressed, covered with plates ; 

 front hollowed with a large longitudinal furrow ; jaws slightly arched, 

 without dentilations ; two barbies under the chin ; no nuchal plate ; 

 sternum wide, imtnoveable ; feet largely palmated, the posterior ones 

 carrying at the heels two large but delicate rounded scales ; tail short, 

 not unguiculate. 



P. expanta. It lives in streams and rivers. P. Dumeriliana. 



Pentonyx, Dum. and Bib. Head large, depressed, covered with 

 plates ; muzzle rounded ; jaws slightly arched, trenchant ; two 

 barbres under the chin ; no nuchal plate ; sternum immoveable ; five 

 claws on all the feet ; tail moderate, not unguiculate. 



P. Captruii ; P. Adanionii. 



Strmiitherut, BelL Head depressed, furnished with great plates ; 

 jaws without -dentilations ; no nuchal plate; sternum wide, with very 

 narrow lateral prolongations ; free anterior portion of the plastron 

 rounded, moveable : five claws on each foot. 



S. niger ; S. nigricant ; S. cattaneiu. 



Platfmyt, Wagler, as reformed by Messrs. Dum<!ril and Bibron, com- 

 prising part of llydratpit of Gray, Plattmyi, Rhinemyt, and Phrynopt 

 of Wagler. Head flattened, covered with a single delicate scale or 

 with a great number of small irregular plates ; jaws simple ; two 

 barbies under the chin ; carapace very much depressed ; sternum 

 immoveable ; five claws on the fore feet, four on the hind. 



It embraces the following species : P. Martmdla (Brazil and 

 Cayenne) ; P. Spirit (Brazil) ; P. radiolata (Brazil, where it lives in 

 the marshes) ; P. gibba ; P. Gcoffrta.no. (young sent from Buenos 

 Ayres by M. d'Orbigny) ; P. Waglerii (Brazil) ; P. Nieuwiedii (Brazil) ; 

 P. Gaudichaudii (Brazil) ; P. HUarii (Brazil) ; P. Miliatii (Cayenne) ; 

 P. rufiprt (Brazil, banks of the River Solimoens); P. Schweiggerii 

 (South America) ; P. Marquaria (Macquarie River, Australia). 



Ckdodina, Fitzinger. Head very long and very flat, covered with 

 delicate skin ; muzzle short, gape wide, jaws feeble, without dentila- 

 tions ; no barbies to the chin ; neck very much elongated ; a nuchal 

 plate, plastron immoveable, very wide, rounded in front and solidly 

 fixed on the carapace ; sternal alte very short ; intergular scale larger 

 than each of the gulars ; four claws on each foot ; tail excessively 

 short. 



C'. Novce Hollandice ; C. Jtarilabris ; C. Maximiliani. 



Chtlodina 



Holtanditr. 



Chflys, Dum. and Bibr.* Head much depressed, wide, and triangular ; 

 nostrils prolonged into a proboscis ; gape wide, jaws rounded, of but 

 little thickness ; neck furnished with long cutaneous appendages, 

 two barbies to the chin ; a nuchal plate ; five claws on the fore feet, 

 four on the hind feet. 



The gape extends beyond the ears. Messrs. Dum<5ril and Bibron 

 remark that the jaws are rounded, narrow, and not simply covered 

 with soft skin, as Cuvier, Wagler, and Gray believed, but protected 

 by horny cases, like those of all the othtr Chelonians ; only in CMyi 

 they are extremely delicate. 



C. Matamata. It lives in stagnant waters. A female lived some 

 months at Paris and laid three eggs, one of which was hatched and 

 the young animal preserved in the Paris Museum. 



C'lulyx Jlalamttm, 



Family III. Potamians, m- River-Tortoises. 



The species belonging to this family live constantly in the water, 

 only coming out occasionally. 



It would seem that individuals of this family attain a large size. 

 Messrs. DumeYil and Bibron quote Pennant as mentioning some 

 which weighed TOlbs. ; one which he kept three months weighed 

 201bs., and ite buckler was 20 inches in length, not reckoning the 

 neck, which measured 13J inches. Their mode of life and habits 

 seem to have great similarity. They swim with much ease both on 

 the surface and at mid-water. The lower part of their body 

 generally pale white, rosy, or bluish ; but their upper parts vary in 

 their tints, which are most frequently brown or gray, with irregularly 

 marbled, dotted, or ocellated spots. Straight or sinuous brown, 

 black, or yellow lines are disposed symmetrically on the right and 

 left, principally on the lateral parts of the neck and on the limbs. 

 During the nights, and when they believe themselves to be secure 

 from danger, the Potamians come to repose on the islets, the rocks, 

 the fallen trunks of trees upon the banks, or floating timber, whence 

 they precipitate themselves in the water at the sight of man or at 

 the least alarming noise. They are very voracious and agile, and 

 pursue, as they swim, reptiles, especially young crocodiles and fishes. 

 Their flesh being esteemed they are angled for with a hook and line 

 baited with small fish or living animals, or with a dead bait, to which 

 the angler gives motion and apparent life ; for they are said never to 

 approach a dead or immoveable prey. When they would seize their 

 food or defend themselves they dart out their head and long neck 



