CAIMANOIDEA VISHERI, A NEW CROCODILIAN 



55 



mandibular tooth fits into a deep pit in the palate instead of closing 

 in a notch, as in crocodiles. Furthermore, all the mandibular 

 teeth close within those of the upper jaw. In the lack of a division 

 of the anterior nares and the lateral union of the dorsal scutes, the 

 form is quite similar to the genus Crocodilus. It apparently stands 

 much nearer to Caiman, however, than to either of the genera 

 mentioned above inasmuch as this group 

 combines the alligatoroid bite, the un- 

 divided anterior nares, and the lateral 

 union of the dorsal scutes. One of the 

 striking differences from Caiman is to be 

 seen in the entire lack of the anterior 

 border of the external narial opening in 

 the form here described. A new genus, 

 Caimanoeda, is proposed to include this 

 form C. Visheri, which may be considered 

 the type, and C. (Crocodilus) prenasalis, 

 Loomis, 1 a form that a careful examination 

 of the type skull has shown to be very 

 similar to C. Visheri. 



, If one may depend on the figures of 

 C. prenasalis there is a noticeable differ- 

 ence between the dorsal scutes of this 

 form and those of C. Visheri. In the 

 latter, all the scutes are more or less 

 strongly keeled, and are much more finely 

 and regularly pitted than in the former. 

 Greater differences are to be noted in the 

 vertebrae. Of the vertebral column of ment of dorsal armor in 



^ t • T • i™, , transverse rows, about three- 



C. prenasalis Loomis says : The vertebrae fourths natural size- 

 are all deeply procoelous. Those of the 



lumbar region have heads (posterior) which are short, wider than 

 high, and rectangular in outline. Those of the dorsal region, how- 

 ever, are smaller and have prominent conical, rounded heads." 



As pointed out above, in the lumbars of C. Visheri, the posterior 

 face of the centra are regularly convex and round in outline and the 



1 Op. cit. 



Fig. 



Visheri, 



4. — Caimanoideus 

 apparent arrange- 



