﻿NEW CRETACEOUS AND EOCENE FOSSILS. 2S7 



The largest species of VolutUithes probably yet discovered. On the ridge below the 

 suture are oblique plications or irregular lines, some of which are acute. 



ACTION, Mont. 



Action modicellus. Elliptical, very small ; rather thick in substance ; revolving 

 lines impressed and striato-punctate ; columellar plait obtuse ; spire conical. 

 Locality. — Tippah Co., Mississippi. Dr. Spillman. 

 A very small species requiring a lens to distinguish its sculpture. 



TURBONILLA. . 



Subgenus CHEMNITZIA. 



Shell conical or elongated, broad at base and rapidly tapering to the apex ; aperture 

 acutely oval or elliptical. 



The shells of this subgenus are very large, and broad in the body whirl compared 

 with the recent species of Turbonilla, and characterize the Cretaceous strata, not 

 one, at least in America, having survived that period. 



T. (Chemnitzia) corona. PI. 46, fig. 50. Turrited, whirls carinated above the 

 suture, which is profound ; 3 robust revolving undulated lines on each volution, with 

 a plain space above ; whirls profoundly coronated on the upper margin. 



Locality . — Tippah Co., Mississippi. Dr. Spillman. 



A fragment, with three whirls, is all I have seen of this magnificent shell, one of 

 the largest and certainly the most elegant species of the subgenus Chemnitzia yet dis- 

 covered. Behind the remarkable coronation of the volutions there is a profound 

 channel, and the carina above is tuberculous. The outline of the aperture is not 

 exhibited in the fragment. 



T. (Chemnitzia) Spillmani. PL 46, fig. 48. Conical-elongate ; whirls with straight 

 sides ; obtusely costate, costae broad, approximate ; revolving lines on each whirl four 

 in number, distant, impressed. 



Locality.— Occurs with the preceding. Dr. Spillman. 



A fragment, consisting of three whirls and broken at the base. 



Although I have grouped these beautiful fossils in a subgenus, I believe they are 

 generically distinct from Turbonilla as founded on small existing shells. I have 

 retained the name Chemnitzia, although not applied by D'Orbigny to characterize 

 especially this fossil group, in order to retain the name of one of the fathers of Con- 

 chology. 



T. (Chemnitzia) melanopsis. PL 46, fig. 35. Subulate, whirls nine, flattened on 

 the sides ; ribs angular, slightly curved, about seventeen in number on the body 

 whirl ; revolving lines distinct, unequal, about seventeen in number on the penul- 

 timate whirl ; suture impressed, slightly waved ; aperture long, elliptical. 



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