6. CAIMAN. 297 
Champse gibbiceps, Natterer, 1. c. pl. xxviii. 
Caiman palpebrosus, Gray, Cat. Tort. 8c. p. 67 (1844), and Sh. 
Rept. ii. p. 28 (1872). 
gibbiceps, Gray, Cat. Tort. Sc., p. 67. 
Alligator palpebrosus, Strauch, Syn. Crocud. p. 25 (1866). 
19 or 20 upper and 20 lower teeth on each side ; third and fourth 
maxillary teeth largest. Head once and three fifths to once and 
two thirds as long as broad; snout subacuminate, its basal width 
contained about once and a half in its length ; no cross-ridge in front 
of the interorbital region, which is but slightly concave; upper 
eyelid flat and smooth, entirely bony, the bony plate consisting of 
four distinct pieces; leres very steep and high ; canthus rostralis 
angular; supratemporal fossze obliterated. ‘Two transverse series 
of postoccipital scutes, followed by four or five transverse series of 
large, very highly and sharply keeled nuchals, the second and third 
usually composed of three or four scutes, the others of two. Dorsal 
scutes in 18 or 19 transverse series, the broadest of which are 
composed of six or eight scutes, which are less highly keeled than 
in the preceding species ; those between the hind limbs constantly 
in four longitudinal series. The caudal crest becomes single on the 
twelfth or thirteenth verticil. Dorsal and ventral bony armour 
much developed; sides of body soft, with scattered small bony 
tubercles ; gular and outer ventral scutes keeled. Fingers free, toes 
webbed at the base. Yellowish-brown above, spotted and cross- 
barred with black. 
Total length 1 m. 20 centim. 
Guianas and Brazil. 
a,b. Ad. & hegr., stffd. ? 
ec, d. Yg., spir. —P 
The precise affinities of the following Crocodile are uncertain, as 
the original description does not give the number of the mandibular 
teeth ; and as, in the unique specimen upon which the species is 
founded, the fourth mandibular tooth on one side is received into a 
notch as in true Crocodiles, and on the other into a pit, as in the 
Alligators, it is difficult to say to which group it belongs, although 
Cope suspects its affinities to be ‘‘rather more Alligatorial.” It 
also appears to me doubtful whether the absence of the claw in the 
third finger will prove a constant character. 
PEROSUCHUS. 
Cope, Proc. Ac. Philad. 1868, p. 203, and Tr. Am. Phil. Soe. (2) 
xiv. p. 83 (1870). 
“Toes 5—4, with claws two—three. No osseous nasal septum or 
bony eyelid. Belly protected by series of osseous plates, as well as 
the back.” 
