MARYLAND GEOLOGICAL SURVEY 87 



in that form, the root extends high up on the inner face, but is low on 

 the outer. 



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

 ent river. 



Collection. — Philadelphia Academy of ISTatural Sciences. 



Carcharias incidens n. sp. 

 Plate XXXII, Fig. 8. 



Description. — Teeth robust, triangular, prominently serrated along 

 the entire coronal margin on both sides. Posterior margin only slightly 

 concave, the anterior nearly straight. Eoot deep, not produced beyond 

 the base of the crown on either side. 



The unique example on which this species is founded resembles in 

 general form certain species of Corax from the Cretaceous, and is read- 

 ily distinguished from other teeth pertaining to Carcharias, the roots 

 of which are expanded and the coronal margins less prominently and 

 completely serrated. The form under consideration also bears some 

 resemblance to that described by Noetling as Galeocerdo duhius, from 

 the Prussian Eocene.' Both faces of the crown are convex, the inner 

 more so than the outer. The total height of the tooth is 14 mm., the 

 width 15 mm., and thickness of the crown at the middle of the base 

 4 mm. 



Occurrence. — Calvert Formation. Chesapeake Beach. 



Collection. — Maryland Geological Survey. 



Genus GALEOCERDO Muller and Henle. 



Galeocerdo contortus Gibbes. 

 Plate XXXII, Figs. 9a, 9b. 



Galeocerdo contortus Gibbes, 1849, Jour. Acad. Nat. Sci. Phila., 2nd ser., vol. i, p. 



193, pi. XXV, figs. 71-74. 

 Galeocerdo contortus Clark, 1895, Johns Hopkins Univ. Circ, vol. xv, p. 4. 

 Galeocerdo contorttis Clark, 1896, Bull. 141, U. S. Geol. Survey, p. 62. 



Description. — " A species of moderate size. Teeth very robust, with 

 elevated crown; the apex above the posterior notch elongated, produced 



' Abh. geol. Specialk. Preussen u. Thiiring. Staaten, vol. vi, pt. 3 (1885), p. 97, 

 pi. V, fig. 6. 



