FROM THE PHOSPHATE BEDS OF SOUTH CAROLINA. 231 



natural size, I suspect to belong to a Squalodont or to a nearly related genus. 

 It is composed of portions of the frontal, ethmoid, vomer, maxillaries, and inter- 

 maxiUaries all intimately co-ossified. The specimen is black, moderately heavy, 

 and in several positions retains some portions of soft rock, in which the fossil 

 was once imbedded, and on which are several casts of lamellibranchs, whose 

 characters are too obscure to determine whether they are of miocene or earlier 

 forms. Besides the fossil shells the specimen exhibits a number of attachments 

 of recent barnacles and oysters, indicating that it had been exposed to the action 



of the present sea. 



The specimen as preserved appears bilaterally symmetrical, except so far as the 



regularity has been disturbed by accident. 



The back portion of the vomer exhibits a comparatively capacious groove for 

 the mesethmoid cartilage. The mesethmoid bone forms a thick partition separat- 

 ing the bloAvholes, and ends in a stout tuberosity at the commencement of the 

 supra-vomerine canal. 



The forehead as formed by the frontal is remarkably long fore and aft compared 

 with its usual condition in the Cetaceans. At the occipital boundary it forms a 

 transversely concave line, and the sutural border of the frontal in this position, 

 from the exterior to the cranial cavity, is about an inch in thickness. The fore 

 and aft length of the forehead is two inches, its breadth between the infra-orbital 

 fossee scarcely 2^ inches. The surface of the forehead is nearly flat, but slightly 

 convex laterally and towards the fore part. The nasals appear to have articulated 

 at the fore part of the frontal and have been detached and lost, though it may be 

 that what I have considered to be the frontal may in part consist of the co-ossified 

 nasals. If the latter view is true, I cannot determine the extent of the nasals as 

 all traces of their outline have been obliterated. The premaxillaries in the speci- 

 men appear to have been destroyed so far as to leave the supra-vomerine canal 

 widely exposed. Their posterior part is comparatively narrow where it bounds 

 laterally the blow-holes, and ends in a point extending three-fourths the length of 

 the forehead between the frontal and the expanded supra-orbital portion of the 

 maxillary. Just within the position of the suture defining the premaxillary later- 

 ally from the maxillary, a narrow groove extends forward to the broken extremity 

 of the fossil. 



The supra-orbital fossse appear to have been symmetrical, and exhibit nothing 

 unusual. Prenarial fossae on the premaxillaries can hardly be said to exist. 



The under surface of the fossil exhibits the frontal roof of the cranial cavity, 

 together with two holes broken through the ethmoid into the nasal passages. The 



