106 PALEONTOLOGY OF NEW JEESEY. 



one-fourth of an inch to five-sixteenths of an inch in length, and are pro- 

 portionally much more slender than are those of that species. They also 

 possess a greater number of vertical lines, and two additional spiral lines 

 on the body whorl. The surface features are much like those of that 

 species, but on many of them the spiral lines are more distinctly raised ribs, 

 and the line of nodes below the suture more distinctly separated from and 

 proportionally larger than those below. The thickened outer lip is the same 

 as on that shell, as also is the lip-like varix within the limit of the body 

 whorl, but the teeth-like ridges on the columella and on the inside of the 

 outer lip appear on most specimens somewhat stronger in proportion to the 

 size of the shell, while the proportional length of the spire, as compared to 

 that of the body whorl, is considerably greater. These features are so marked 

 as to render it unsafe to include these specimens under the same specific 

 head with T. trivittatoides. 



Formation and locality: In the gray Miocene marls, at Shiloh and 

 Jericho, N. J. From th e collection of the National Museum. 



Tbitia bidentata. 



PI. xix, fig. 7. 



Buccinum bidentatum Emmons: K Car. Geol. Surv-., 1858, p. 257, fig. 126. 

 Tritia bidentata Conrad: Proc. Acad. Nat. Sci. Phila., 1862, p. 562. Meek, Check List 

 Miocene Foss., p. 20. 



" Shell quite small, thick, robust; whorls about five, two upper smooth, 

 the others are ornamented with ribs and spiral bands; aperture oval, acute 

 behind, outer lip furnished with two rather prominent teeth or short ridges; 

 canal wide and very short." (Emmons.) 



This shell differs from the two others of this type occurring with it 

 in its size and proportions, this one being shorter and more robust than 

 either of the others, the volutions more inflated and ventricose and often 

 six in number, and the teeth in the aperture several. As compared 

 with T. trivittatoides, the size alone is quite sufficient to distinguish it, 

 but when compared with the elongated variety, which is more nearly like 

 this in size, the rotundity o f the volutions and its short broad form needs 

 examination. In this one the longitudinal folds are stronger and rounder, 



