72 THE WASATCH AiN'D BEIDGEE FAUN^. 



Dapedoglossus acdtus Leidy. 



Phareodui acutui Leidy, Proceed. Acad., Phila., 1873, p. 99; Final Report U. 8. GeoL Surv. Terra., i, 



p. 193, Plate 32, figs. 47-51. 

 Pkareodon acutiu Leidy, Cope, part. Annual Report U. 8. Geol. Surv. Terrs., 1872 (1873), p. 637. 

 Phareodon tericeut Cope, 1. c, p. 63!^. 



Plate V, figs. 18-20. 



Represented by numerous remains. The teeth, as preserved, are black 

 with white ti-anslucent slightly incui-ved apices The dentary bones are 

 deep, incurved, and with an erect elevated point at the symphysis; their 

 outer surface is rugose with deep longitudinal grooves and pits of irregular 

 sizes. They are narrow transversely, and support a single series of twenty 

 two or three closely placed slender teeth, which together form a comb. 

 The bases of these teeth are nigose-striate, and the apices abruptly acumi- 

 nate. 



Measurements. 



li. 



Depth of dentary at symphysis 009 



Depth of dentary at fourteenth tooth 015 



Length of eighth tooth 0056 



Diameter of eighth tooth at base 0015 



Six teeth in 0100 



The palatine bones support a mass of teeth, there being one external 

 series of large ones rather abruptly pointed, and several series of small 

 ones of little elevation, whose size diminishes inwards. On two teeth of 

 the external series of a large individual, I proposed the species Phareodon 

 sericeus, with the following description : "They differ from those of the 

 P. acutus in their large size and stout conic form ; also in having the basal 

 Btriation finer, parallel, and extending over half the length of the crown. 

 The basal portions as preserved are black, the apex white, and with a 

 slightly abrupt contraction." 



Measurements. 



The specimens of Dapedoglossus acutus which I have seen, I obtained 

 from the upper valley of Green River, from the marls of the Bridger epoch. 



