NATURAL SCIENCES OF PHILADELPHIA. 191 



depressed. Both these specimens are young and have lost their epiphyses ; 

 with the latter, they would be relatively as slender as those ofD. lacertosus; 

 they differ from the latter in their deep lieel, like that of a boat. 



A dorsal vertebra is with much probability referred to the same species. It 

 is therefore a little shorter than the lumbars and has not so strong a keel ; yet 

 the latter is more marked than in any other species, contrasting much with the 

 round face of the D. la c e r t o s u s. It is adult with fixed epiphyses ; the articu- 

 lar faces are subround. The upper part of the diapophyses come from the base 

 of the neural arch, and the neural canal is wide, with median ridge as usual. 



In. Lin. 



Length, dorsal, centrum 2 11-5 



Depth articular face 2 0-5 



"Width of " " 2 2-5 



" " centrum at base transverse margin of diapophysis 2 10-3 



Length centrum lumbar 3 6 



Width in front diapophysis 2 5-2 



" of " I 10-5 



Depth centrum from canal to edge of keel 1 10-5 



This species is named for my friend B. Waterhouse Hawkins, the restorer of 

 the extinct mammals and reptiles at Sydenham Palace, England, who is now 

 engaged in the Museum of the Academy on a similar work-for the Central Park, 

 New York. 



Delphi.\apter0s gabbii Cope. 



This species is indicated by a well preserved caudal vertebra of an adult, 

 which is so different from anything else in our Museum as to require notice. 

 It has pertained to a species of not more than half the length of the T. 

 gr an d a e v u s, and is less strongly constricted everywhere and especially 

 below. In a caudal of near the same position, the ridges and chevron artic- 

 ular surfaces are much more elevated, especially those on the anterior part of 

 the centrum. The}' embrace a very deep groove in this, a shallow one in the 

 T. gabbii. An additional longitudinal ridge on each side the inferiors in 

 front is wanting in T. gabbii. Both have a delicate one above the dia- 

 pophyses in front, the T. grandaevus behind also. There is no posterior 

 zygapophysis in the T. gabbii; the caudal of the latter is also relatively 

 shorter. 



In. Lin. 



Length centrum » 2 



Depth articular face anterior 1 5-7 



Width " " " 1 7 



This species is dedicated to my friend Wm. M. Gabb, Paleontologist of the 

 State Geological Survey of California. 



To this genus belongs also the Priscodelphinus grandaevus of Leidy. 

 This species is not rare in our collections. 



I may add that there still remain species of DelphinidiB in the collection 

 which are as yet undescribed. 



The vertebi'ae of several rather small species of this family were procured 

 by J. T. Thomas, of which a few are sufficiently characteristic for descrip- 

 tion. They are accompanied by the other bones of the body, but as these 

 must be allocated with much care and labor, and as the vertebrje are most 

 abundant and therefore characteristic of the beds, I think best to describe 

 them from these. 



ESCHRICHTIDS Gray. ' 



ESCHRICHTIDS PUSILLUS CopC. 



This species is indicated by many vertebrae, of which one dorsal, six of the 

 1868.] 



