778 CRETACEOUS PALEONTOLOGY. 



Volutoderma abbotti (Gabb). 

 Plate XCIL, Figs. 1-2. 



1860. Volutilithes Abbotti Gabb, Proc. Acad. Nat. Sci. Phil. 



(1860), p. 94, pi. 2, fig. 7. 



1861. Volutilithes Abbotti Gabb, Synop. Moll. Cret. Form., p. 



149 (93). 

 1864. Volutilithes ( ?) Abbotti Meek, Check List Inv. Foss. N. 



A., Cret. and Jur., p. 21. 



1868. Volutilithes ( ?) Abbotti Con., Cook's Geol. N. J.. p. 729. 

 1876. Volutomorpha Abbotti Gabb, Proc. Acad. Nat. Sci. Phil. 



(1876), p. 293. 

 1892. Volutoderma Abbotti Whitf., Pal. N. J., vol. 2 (Monog. 



U. S. G. S., vol. 18), p. 173, pi. 21, figs. 4-9. 

 1905. Volutoderma abbotti Johns., Proc. Acad. Nat. Sci. Phil. 



(1905), P- 2 5- 



Description. "Shell of medium size, elongately oval in gen- 

 eral outline, with a very short spire and large body volution 

 which forms nearly the entire bulk of the shell, and which is 

 nearly evenly convex above and below the middle. Volutions 

 about four in number; suture line not very distinct. Aperture 

 long and narrow, rather more than two-thirds as long as the 

 shell and pointed above and below. Columella comparatively 

 strong, marked by three or four very oblique folds of moderate 

 strength. Surface of the shell unknown, all the specimens rec- 

 ognized being internal casts." (Whitfield.) 



Remarks. There seems to be some doubt as to the proper 

 horizon of this species. Gabb described it from "Burlington 

 Co., N. J.," which allows a very wide range of horizons from 

 which it might have come. Whitfield states that the lithologic 

 character of the specimens indicate that they are from the Tim- 

 ber Creek beds, which would make their horizon Vincentown. 

 The shell resembles V. biplicata, but is much more slender and 

 the columella is furnished with a larger number of folds, there 

 being only two in V. biplkata, while in this species there are 

 three or four. 



Formation and locality. Uncertain. 



Geographic distribution. New Jersey. 



