December 10, 1915 Vol. V, pp. 103-106 



PROCEEDINGS 



OF THE 



NEW ENGLAND ZOOLOGICAL CLUB 



ON THE IDENTITY OF PEROSUCHUS COPE WITH 

 CAIMAN SPIX. 



BY HENRY W. FOWLER. 



For many years the genus Perosiichus has remained much of a 

 puzzle. It was first characterized ^ in 1868 for the monotypic P. 

 fuscus, the type specimen being an alcoholic skin, with head and 

 feet entire (no. 9720, Academy of Natural Sciences of Philadelphia). 

 At the suggestion of Dr. Thomas Barbour, who examined the type 

 recently, while in Philadelphia, I have prepared this note, in order 

 to point out its true relationship. The generic characters used by 

 Cope for the definition of Perosuchus are chiefly the presence of 

 five toes on the fore limbs, each with but two claws, and of four 

 toes on the hind limbs, each with but three claws. The absence of 

 a bony nasal septum, and of bony eyelids, is also noted. Cope 

 admits that "the free fingers and half-webbed toes, and the bony 

 abdominal buckler, together with the cartilaginous nasal septum 

 are all points of strong resemblance to Jacare (Gray, including 

 Coeman Gray), but it differs from these creatures in the lack of 

 bony orbital plate." The type specimen, which is evidently an 

 abnormal example, justifies Boulenger's remark that "it also 



iProc. Acad. Nat. Scl. Phila.. 1868. p. 203. Magdalena River, Colombia. 



