EASTMAN : TYPES OF FOSSIL CETACEANS. 81 



the cervical vertebrae. The latter, with the exception of the atlas, which remains 

 adherent to the occiput, are not mentioned in the original description nor in any 

 subsequent notice of the specimen. On the other hand, the principal features of 

 the skull are well signalized by both Harlan and Cope, from the former of whom 

 we quote as follows : — 



" This interesting fossil consists of the skull, nearly complete, densely petrified, 

 very weighty, tinged of a deep black, ferruginous color ; characteristic marine 

 fossil shells adhere to its base. . . . The external border of the superior maxillary 

 bones is slightly broken on each side. Its discovery is due to the active researches 

 of Mr. Francis Markoe, Jr., Corresponding Secretary of the National Institution, 

 who obtained it from the Calvert cliffs, on the right bank of the Chesapeake bay, 

 State of Maryland, along with other characteristic fossils. . . . 



" The present specimen belongs to Cuvier's first subgenus, or " les Dauphins a long 

 bee" [= type of Champsodelphis Gervais]. On comparison witli the numerous 

 species of living dolphins, it is found distinct from all of them. It approximates 

 the Delphinapterus leucorampus, of Peron, 1 but differs in its various measure- 

 ments, number of teeth, and in the arrangement of the palatine bones. . . . 



" Description of D. Calvertensis. — In general outline, resembling other skulls of 

 this genus. The head is proportionally narrower, and snout more elongated, than 

 the Italian specimen with which I have compared it. The occipital and temporal 

 ridges are strongly developed, indicating muscular strength, especially of the jaws. 

 We find similar indications in the remains of the teeth, which have been large and 

 robust. There are ten sockets remaining on the right side, with the teeth broken 

 off at the rim. These organs approximate each other. The ten sockets include a 

 line four and a half inches long. There has been about one and a half inches of 

 the end of the snout broken off, which would afford room for two or three more 

 teeth, making twelve or thirteen in all, on each side. The pyramidal eminence 

 anterior to the posterior nares, on the palatine surface, is strongly pronounced. It 

 terminates opposite the last tooth. The excavations or longitudinal grooves, on 

 each side of the upper portion of this eminence, are unusually deep. The palatine 

 surface is slightly convex transversely. Above, the head is narrower across the 

 occipital ridges than other allied species, and narrower than the transverse diam- 

 eter of the base of the skull. The ossa nasi are longer than broad, and convex. 

 The atlas vertebra adheres to the occiput, above the condyles. It measures, across 

 the transverse processes, five inches; transverse diameter, three inches; and the 

 ring is about one inch thick." — (p. 196). 



In connection with the above description, the following measurements are 

 given, to which we have added their metrical equivalents in parentheses. The 

 author states in regard to the missing portion of the rostrum that " one and a 

 half inches must be considered as the length of the last portion of the extremity 

 of the snout." 



Dimensions : 

 Total length of head, from the temporal crest to the presumed 



extremity of the jaw 17 in. (432 mm.) 



1 Vide Cuvier, Ossemens Fossiles, 5,pt. 1, p. 289, Plate 21, Figs. 5 and 6, ed. 1823. 



VOL. LI. — NO. 3 6 



