261 



lik(! must of IIr' otliLT i'ostiiLs aecoinpauyiiig them, are tliuroiighl}- saliiratcd 

 with bitumen. 



Tiie most characteristic specimens consist of two isolated cpisterna, repre- 

 sented in Fig. 7, Plate IX. They indicate an animal al)()ut tin? size of the 

 recent Emys scabra of the Southern States, but the hones are proportionately 

 more robust tlian in that species. They abruptly project in advance of the 

 lateral grooves defining the gular scutes, antl are squarely Iruneate'd. Tiie 

 upper gular surface is nearly square, and slopes forward to an acute edij:e. 

 In one specimen it is wider fore and aft than transversely; in the other rather 

 less. Behind the gular surface, the bone is deeply hollowed into a concavity. 



The measurenients of the specimens are as follows : 



Wkltli of episternal at the front bonlor ... I 10 



Length of internal border 11 



Leugtli of po.stero-lateral border 12 



Greatest thickness of tlie bone j 5J 



A hyposternal bone about the middle is 28 lines fore and aft, 26 lines wide 

 behind the inguinal notch, and half an inch where thickest internally. 



The fore part of a nuchal plate of the carapace resembles the corres|)on(l- 

 ing portion in Emys scabra, but is more deeply indented. Its width in IVont 

 is an inch; the length of its median ridge is 10^ lines; and its thickness where 

 greatest is half an inch. 



FISHES. 



The following species of extinct fishes were first described by the writer 

 in the Proceedings of the Academy of Natural Sciences of Philadelpliia iiir 

 June, 1870. Tiie specimens were borrowed for my examination from a 

 gentleman ot New York, by my friend Mr. George N. Lawrence, of the 

 same city. The locality of the specimens was not ascertained other than 

 that they came from the Rocky Mountains. They were accompanied with 

 some shells, evidently of the later Tertiary period, and also with a coronary 

 bone, apparently of Equus exceisiis. The fish-rcmains consisted of eight 

 detached i)haryngeal bones of a cyprinoid. and a single dermal bone of a ray. 



Subsequently, while a notice of these fossils was in press, the writer 

 received from Professor Hayden a pharyngeal bone of the same species and 

 ap[>earauce as the Ibrmer, which was labeled "Castle Creek, Idaho." 



