64 THE WASATCH AND BRIDGEE FAUN^. 



Measurements. 



X. 



Width frontal bono near firont of fontanelle 0.012 



Thickness at same point 004 



Thickness of casque 004 



Width spine 005 



Depth spine 009 



The single individual of this species whose remains are preserved 

 shows that it was the most robust, though not the largest of the genus. I 

 found it on South Bitter Creek in the Washakie basin of the Bridger forma- 

 tion. 



Rhineastes SMiTHii Cope. 



Proceed. Amer. Philos. Soc., 1872, p. 486 (August 20). Annual Report U. S. Qeol. Snr\-. Terrs., 1872, 



p. C39 (1873). 



Plate V, figs. 5-11. 



Represented by remains of several individuals, including one with 



vertebrae, basioccipital, opercular and other cranial bones, with spines. 



They indicate a fish of the size of the large catfishes of the Ohio River. 



The pectoral spines are quite compressed and distinctly striate-grooved on 



the sides. The posterior groove is occupied by short, spaced, recurved 



teeth ; the anterior by an acute edge, bounded by a gi-oove on each side, 



which has a fine, close serration. The surface of the modified vertebral 



mass is sti'iate ridged ; that of the basioccipital still more strongly ridged. 



In the latter there is a median pit behind, and the points of attachment of 



the inferior limb of the post-temporal is in front of it, smooth, and without 



reverted edges. The operculum has a large compressed, sessile cup, and its 



external .surface is strongly ridged and grooved, radiating from above in 



front. 



Measurements 



u. 



Diameter of a vertebra 021 



Length of centrum 009 



Diameter of moditicd vertelirn 013 



Diameter of groo vo of vertebra 005 



Diameter of occipital articulation 015 



Length of cup of operculum 013 



Diiimeler of spine at base 008 



Diameter of spine at .004 from base 0037 



Another pectoral spine is larger; diameter at base .010. 



From the Mammoth Buttes and Laclede, on South Bitter Creek.* 



• Named for my respected friend, Daniel B. Smith, of Gerraantown, Philadelphia, many years 

 principal of Haverfurd College, ond a student and lover of natural sciences. 



