•iS-i 0. a Marsh— New Fossil Reptiles from 



Crocodilus Iwdorij sp. nov. 

 A second small species of Crocodile is indicated bv thp v^'^y.^- 

 important parts of a skeleton from the same Tertiary d. 

 as the preceding species. In this specimen the teeth are > 

 nearly round at the base, slender, with compressed points, 

 cutting edges are prominent and sharp, but not serrate il. 

 jaws are quite slender. The quadrate is short, concave 

 upper surface, arid very flat at its distal end. The u?ua 

 matic foramen on the inner superior margin is, in tlii- 

 men, wanting or rudimentary. On the lower surface tli<- 

 broad longitudinal elevation, which is mainly outside th. .. 

 dian line. The basioccipital is stout, and uniformly eoii\ < \ 

 transversely. The axis is elongated, and rather slender. The 

 hypapophyses of the cervicals are simple, compressed, and i^on- 

 gated. In the anterior cervicals they are directed forward, but 

 in the eleventh vertebra, this process is perpendicular. The 

 articular cup is here a very broad transverse oval. The dorsal 

 scutes were articulated. 



Transverse diameter of quadrate, at distal end, 14- hne% 



Vertical diameter, on median line, 3-90 " 



Length of axis, with odontoid process, - - 22-25 



Length of eleventh vertebra, from ed^e of cup to end of 



ball, 16- " 



Width of cup,.-- 9- I' 



Depth of cup, 8-10 'J 



Length of hypapophysis, 5* 



This specimen was nearly, but not quite, adult. It was dis- 

 covered by Mr. C. T. Ballard, of the Yale party, at Grizzly 

 Buttes, near Fort Bridger. 



Crocodilus affinis, sp. nov. 



The most common fossil Crocodiles in the Tertiary beds ot 

 Western Wyoming are large reptiles, having stout conical ru- 

 gose teeth, with prominent, but rather obtuse cutting edges. 

 not unlike the teeth of the modern North American Alligator- 

 Professor Leidy has recently described, under the name oi 

 Crocodilus MUotti* a species with these characteristics, \vbicn 

 was found in the eastern part of the same Tertiary lake-basin • 

 but a comparison of his original specimens, which he has km' .^^ 

 loaned the writer for this purpose, with the extensive materia- 

 obtained by the Yale party near Fort Bridger, show clear ^ 

 that there are two distinct species, about the same size, and wu 

 teeth almost identical. The two may be distinguished, now 



, PhU., 1870, I 



