SAURIA. 17 



fourth lower ones entering into holes in the upper jaw, and not into 

 notchesj their feet are only semi-palmate and without emargination. 

 They have hitherto only been certainly found in America. 



Croc, sderops, Schn.j Seb. I, civ, 10; Cuv. Ann. Mus. X, 1, 

 7 and 16 and 11, 3 (The Spectacle Alligator), so named from 

 a transverse ridge, which unites in front the salient borders of 

 its orbits, is the most common species in Guiana and Brazil. 

 Its neck is defended by four transverse bands of strong plates. 

 The female lays in the sand, covers her eggs with straw or 

 leaves, and defends them courageously. (l) 



Croc. lucius, Cuv.; Caiman d museau de brocket, Ann. Mus. 

 X, 1, 8 and 15, and II, 4, so called from the shape of its muzzle, 

 is also distinguished by four principal plates on its neck. It 

 inhabits the southern parts of North America, forces itself into 

 the mud in severe winters, and remains torpid. The female 

 deposits her eggs in alternate layers with beds of earth. (2) 



French colonists employ it to designate the species of Crocodile most common 

 about their plantations. The word Alligator is used by the English and Dutch 

 colonists in the same sense. It is a corruption of the Portuguese word Lagarto, 

 which is itself derived from Lacerta. 



(1) There are also several sorts of Caimans or Alligators, which have this trans- 

 verse ridge front of the orbits, and which, like the Crocodiles, allied to the com- 

 mon one, perhaps form distinct species, but difficult to chai-acterize. 



Some of them have a shorter and more rounded muzzle; the transverse ridge 

 concave before, and extending to the cheek on each side. They have thirteen 

 teeth on each side above; their cranium is not widened behind; their body is green 

 dotted, and spotted with black, with black bands on the tail. 



Others have the same kind of head and the same teeth, but their body is black, 

 with narrow bands that are yellowish, as in the Jacarc noir, Spix, pi. iv. 



Others again have a muzzle less broad, and the concave ridge does not extend 

 so far: they have fifteen teetli, and their neck is more completely defended by 

 plates; I should willingly consider them as the Cr. Jissipes of S^ix, pi. iii. 



Finally, there are some with a still narrower muzzle, and the cranium somewhat 

 widened behind, whose transverse ridge is convex in front, and does not extend 

 on the cheek; the ridge of their dorsal plates is less salient, and the bands on 

 their tail are more faintly marked: can they be the Cr. pundulatusoi Spix, pi. ii ' 

 That gentleman, unfortunately, has not insisted upon the characters drawn from 

 the transverse ridge. 



(2) Seethe paper of Dr Harlan, Ac. of Nat. So. of Philad- fV, 242.— Add the 

 Caiman d paupigres osseiises, [Croc, palpebrosus, Cuv.) Ann. Mus. X, pi. 1, 6 and 

 7 and 11, 2; and the Croc.trigonatus, Schn., Seb., I, cv, 3; or the Jacaretinga mos- 

 chifer, Spix, pi. i. The whole thickness of the eye-lid in this species is occupied 

 by three osseous lamellae, of which, in other Crocodiles, there is scarcely a 

 vestige. 



Vol. II.—C 



