GASTEROPODA OF THE LOWER GREEN MARLS. 43 



Formation and locality: In the Lower Green Marls at Holmdel, New- 

 Jersey. Collected by the Rev. Dr. Reiley, and now in the collection at 

 Rutgers College. 



Pyropsis JSTaticoides, n. sp. 

 Plate II, Figs. 5-?. 



Small, obliquely ventricose, broadly naticoid in form, with a low spire 

 and rapidly increasing volutions, the last one of which is more rapidly 

 deflected downwards than the earlier ones and forms the great bulk of the 

 cast, appearing in its outer third almost as if detached from the inner volu- 

 tions of the shell, caused probably by the excessive thickening of the shell 

 at the suture; the columella has been small and the aperture proportion- 

 ally quite large, and of a semicircular form, more pointed below than 

 above; volutions not more than two and a half in number; surface of the 

 cast smooth, with the exception of a few faintly marked vertical folds or 

 wrinkles which show only on the inner or smaller third of the outer volu- 

 tions, and may have been caused by closely arranged varices of growth, 

 but they resemble the folds on a regularly plicated shell. 



The species is peculiar in its naticoid form and in the rapid deflection 

 of the outer portion of the last volution. Had it not been for the form of 

 the aperture and columellar cavity, the cast would be naturally looked 

 upon as that of a Natica or Gyrodes. The appearance of vertical folds would 

 scarcely answer for Natica, but as they occur on only a small area of the 

 outer volution they may be deceptive in their meaning. The cast might 

 answer equally well for that of a species of Bhizocheilus, and the deflections 

 of the last whorl would also agree with some species of that genus, but I 

 am not aware that any species of that form has been recognized as low 

 down as the Cretaceous. It might also answer quite well for a species of 

 Rapa. Dr. Stoliczka figures species of Bapa^ which are quite strongly 

 marked with vertical folds, which would show on an internal cast much 

 more strongly than do these. 



Formation and locality: The specimen bears no label of locality, but 

 possesses all the features of casts from the ferruginous layers of the Lower 



•Ind. Geol. Surv. Pal. Indioa, Cret. Fauna South Ind., vol. 2, PI. xili. 



