MOLLUSCA. 675 



rectly determined ; neither are the lithologic characters sufficiently 

 clear to determine its horizon with certainty, although it appar- 

 ently came from one of the marl beds. 



Formation and locality. Unknown. 



Geographic distribution. New Jersey. 



Scala ? hercules (Whitfleld). 

 Plate LXXVL, Fig. 8. 



1892. Scalaria hercules Whitf., Pal. N. ]., vol. 2 (Monog. U. S. 

 G. S., vol. 1 8), p. 140, pi. 1 8, fig. 12. 



Description. "Shell of large size, robust in proportions, num- 

 ber of volutions unknown but compact, comparatively short, not 

 -very ventricose and closely united at the suture lines ; apical angle 

 20 to 25, giving a rather elongated spire; volutions crossed 

 by from 12 to 14 very strong vertical varices, which form 

 thick rounded ribs, rather closely arranged, and each marked by 

 two rounded tubercles, one just below the upper suture line and 

 the other near the lower suture line; also a central line of smaller 

 ridge-like nodes intermediate between the other two, apparent on 

 the last volution, marking the position of a spiral carina on the 

 center of the volution, while other spiral carinae cross the upper 

 and lower lines of nodes, and on the base of the last volution the 

 usual carina surrounding the umbilicus is also marked by a thick- 

 ening of the vertical ribs, but without forming distinct ribs ; form 

 of aperture and intermediate surface structure undetermined." 

 (Whitfield.) 



Remarks. This species has not been met with in the recent 

 collections, and the original specimens used by Whitfield are very 

 incomplete. The species is a large one and the larger specimen 

 used by Whitfield must have been 100 mm. or more in height 

 and 30 mm. or more in maximum diameter. The vertical ribs 

 upon the volutions of this species are somewhat different than is 

 usual in the genus, they being rounded, thickened ribs and not 

 simply varical lips, the varix having been filled to a solid rib 

 before the growth of the shell had progressed beyond it. The 

 number of varices varies somewhat in the different volutions. 

 The finer markings of the shell are not well preserved in the 



