MOI.I.USCA. 769 



size, the last one ventricose in the upper part, rapidly contracted 

 l>elow and produced anteriorly in an elongate anterior canal; 

 aperture elliptical in form, pointed above and prolonged below; 

 columellar cavity of moderate size, with three slender, oblique 

 plications opposite the middle of the aperture; surface of the 

 volutions marked by strong, ro'Unded, vertical plications or folds, 

 which become obsolete a little below the periphery and are also 

 less distinct upon the outer half of the last volution. About 

 II of these folds are present upon the outer volution of an 

 average example. A plaster cast of the upper h^lf of a shell 

 from a natural mould has about five volutions, the spire is con- 

 ical and turrited with an apical angle of about 75°; suture well 

 •defined ; the volutions o>f the spire strongly angular a little below 

 the middle of the distance between the sutures, the upper sur- 

 face flattened or slightly concave, the angle marked with strong 

 nodes, of which there are about 12 on each volution. Upper 

 surface of the body volution nearly flat, sloping downward from 

 the suture to the angular periphery, which is marked by strong 

 nodes similar tO' those of the upper volutions; below the 

 periphery the surface is gently convex as far as the specimen con- 

 tinues. Surface marked by fine revolving costse, and by lines 

 •of growth which, just below the suture, are as strong or stronger 

 than the revolving costse. The direction of the lines of growth 

 indicate that the outer lip of the aperture was broadly sinuate 

 in its upper part. 



Remarks. — ^The specimen used by Whitfield as the type of his 

 Turbinella verticalis has been carefully compared with the type 

 of Cancellaria dabmnensis Gabb, and the two are certainly spe- 

 cifically identical. The species is not an uncommon one in the 

 Navesink marl, where it has been seen only in the form of 

 internal casts. The external characters of the shell have been 

 determined, so far as they are known, from a plaster cast, taken 

 from a natural mould collected in the Wenonah sand, the internal 

 ■cast of the same example being also' preserved, although in a 

 somewhat imperfect condition. This internal cast, however, 

 shows that the Wenonah specimen is not specifically different 

 from the Navesink shells. 

 49 PAI. 



