MARYLAND GEOLOGICAL SURVEY 85 



Description. — A species only distinguished from C. egertoni by the 

 absence of serrations on the coronal edges. Some teeth have the form 

 of Galeocerdo latidens and G. aduncus, except that there are no denticu- 

 lations. 



kt first sight these teeth might appear to be only worn examples of 

 C. egertoni, or even of Galeocerdo (although the posterior notch is never 

 conspicuous), but a study of numerous specimens shows that in all 

 probability the species is well founded. It is found at the same locali- 

 ties as the preceding form. The original of Plate XXXII, Fig. 2, is 

 one of Cope's type-specimens, and the first of this species to be figured. 



Occurrence. — Calvert Formation. Charles county near the Patux- 

 ent river, Fairhaven. 



Collections. — Maryland Geological Survey, Philadelphia Academy of 

 Natural Sciences. 



Carcharias collata n. sp. {ex Cope MS.) 

 Plate XXXII, Figs. 3a, 3b, 4a, 4b, 5. 



Description. — A species of moderate size, the teeth comparatively 

 stout, with a narrow, usually erect crown, strongly convex on its inner 

 and slightly so on its outer face; apex sometimes slightly curved in- 

 wards or backwards; coronal edges with extremely minute serrations 

 disappearing toward the base. The enamel at base of crown extends 

 much lower down in the middle of the outer than on the inner face. The 

 root is considerably elongated, large and symmetrical. 



The Thomas Collection belonging to the Philadelphia Academy of 

 Natural Sciences contains about forty teeth of Carcharias which were 

 evidently regarded by Cope as indicating a new species, since they 

 bear his MS. label " SpJiyrna collata/' a title which is now made valid 

 by the above description. Fifteen other teeth are preserved in the 

 same collection under a different specific title, also unpublished, but a 

 careful examination fails to reveal any important character by which 

 they may be distinguished from the first lot. All of these specimens 

 are from Charles county. 



Under the name of Prionodon antiquus, two teeth of Carcharias, 

 one with serrated and the other with unserrated edges, were described 



