26 SYSTEMATIC PALEONTOLOGY 



LoPHOCETUs CALVERTENSis (Harlan), 

 Plate XVI, Figs, la, lb, Ic. 



Delphinus calvertensis Harlan. 1842, Proe. Nat. Inst., Bull, ii, p. 195, figs. 1-4. 

 Delphinus calvertensis Dekay, 1843, Nat. Hist, of New York, Zool., pt. i, p. 136. 

 Pontoporia calvertensis Cope, 1866, Proc. Acad. Nat. Sci. Phila., vol. xviii, p. 297. 

 Lophocetus calvertensis Cope, 1867, Proc. Acad. Nat. Sci. Phila., vol. xix, pp. 144- 



146. 

 Lophocetus calvertensis Leidy, 1869, Jour. Acad. Nat. Sci. Phila., 2nd ser., vol. vii, 



p. 435 (mention only). 

 Lophocetus calvertensis Cope, 1890, Amer. Nat., vol. xxiv, pp. 606, 615. 



Description. — " In Lophocetus calvertensis the nasal bones are sepa- 

 rated by a deep fissure. The maxillaries exhibit, on each side in front 

 of the external nares, two oval roughened surfaces, which converge 

 behind the nares. These appear to be insertions, perhaps for cartila- 

 ginous crests, comparable to the bony roofs of Platinista, less probably, 

 for muscles connected with the external meatus. 



" The form of the muzzle is not elongate, as in the known species of 

 Pontoporia, and it is much expanded, proximally, instead of contracted, 

 as in the latter." 



On page 196 of Harlan's paper appears the following description: 

 *' The occipital and frontal 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 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 pala- 

 tine surface, is strongly pronounced. It terminates opposite the last 

 tooth. The excavations or longitudinal grooves, on each side of the 

 upper portion of this emiuence, 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 diameter of the base of the skull. The ossa nasi are 

 longer than broad, and convex. The atlas vertebra adheres to the 



