736 CRETACEOUS PALEONTOLOGY. 



Remarks. — This species may be distinguished from P. mullica- 

 ensis, with which it is associated, by its comparatively shorter 

 and broader form, and by the more numerous vertical node-like 

 folds upon the shell. The surface markings oi the shell have not 

 been observed. _ 



Formation and locality. — Navesink marl, Mullica Hill (169). 



Geographic distribution. — New Jersey. 



Pyrifusus erraticus Whitfield. 



Plate LXXXV., Fig. 16. 



1892. Pyrifusus erraticus Whitf., Pal. N. J., vol. 2 (Monog. U. 

 S. G. S., vol. 18), p. 50, pi. 4, figs. 4-5. 



Description. — "Shell of medium size, a very fine specimen used, 

 measuring i^ inches in length; nearly equally fusiform or 

 biconical in general outline as viewed from the back ; apical angle 

 about 50° ; volutions, about four in number, the last one large, 

 subangular on the periphery, concave above, rounded below the 

 middle, and contracted in the lower part ; upper volutions convex ; 

 suture distinct; aperture elongate; canal short; the volutions 

 crossed by nine or ten vertical plications, which are strong, 

 prominent, and rounded on the larger part of the volution, and 

 but faintly marked on the lower convexity of the last one, becom- 

 ing obsolete before reaching the beak; the entire surface of the 

 shell also marked by beautifully rounded, spiral lines, which are 

 alternately larger and smaller, and very closely arranged; these 

 again crossed by fine transverse lines of growth, which make a 

 broad and rather strong retral curve from the suture to the most 

 prominent part of the longitudinal plications, below which point 

 they again bend forward to the swell of the v.olution below; 

 columella and axis unknown." (Whitfield.) 



Remarks. — In the recent collections of the Survey is a large, 

 but somewhat imperfect internal cast of this species, which must 

 have had a total height of 43 mm. when co'mplete, which is con- 

 siderably larger than Whitfield's type, with a height of but 31 

 mm. The species is a well-marked one and cannot be easily con- 

 fused with any other in the Cretaceous beds of New Jersey. 



