60 PALEONTOLOGY OF NEW JERSEY. 



TrACHYTRITON ? HOLMDELENSE, n. Sp. 

 Plate V, Figs. 16, 17. 



Shell of medium size; spire moderately elevated, having an apical 

 angle of 50° or over; is composed of about five very rotund volutions, and 

 forms fully two-thirds of the entire length of the cast when viewed from the 

 back of the specimen; below the point of greatest diameter the cast is short 

 and the beak only slightly extended beyond the general rotundity of the 

 body volution ; suture lines between the volutions in the cast clear, distinct, 

 and deep; aperture rather broadly elliptical; rounded above; slightly 

 pointed below and straightened on the iimer side below the middle of its 

 height; columella moderately strong and smooth; surface of the cast marked 

 l)y vertical folds, thirteen or fom-teen to the volution; these folds distinctly 

 bend backward in the middle in crossing the whorl, and are again directed 

 forward below, forming a broad sinuosity in crossing the whorl; no evidence 

 of revolving lines discernible on any of the specimens. 



This species may not properly belong to the genus Trachytriton. .It is 

 shorter below the point of greatest diameter of the body volution than 

 any species of that genus with which I am acquainted, and the varices have 

 not quite the character required, as they are all of similar form aiid size, 

 and more sinuate than they ought to be under the genus. The beak has 

 been short and there is no evidence of spiral lines or ridges. It has a more 

 obtuse spire than any of the other New Jersey species of this genus, with 

 rounder volution and deeper sutures. It has much the appearance of Cryp- 

 torhytes flex i cos fata M. & H.,^but the beak has been even shorter than in that 

 one, and the shell less slender, while the columella affords no evidence what- 

 ever of any folds or plica of any kind. Its generic relations are quite uncer- 

 tain, and I shall leave it under Trachytriton provisionally. 



Formation and locality: In the Lower Marl Beds at Holmdel, New 

 Jersey. Collection at Rutgers College. 



1 U. S. Geo]. Snr. Terr., vol. 9, Invert. Pal., p. 367, PI. xix, Pig. 2. 



