1917.] NATURAL SCIENCES OF PHILADELPHIA. 308 



mellar plait on the body is another plait similar to a columellar fold; 

 parietal wall glazed with callus; umbilicus imperforate. 



This genus is well characterized by three conspicuous folds on the 

 inner lip. The most posterior of these folds is situated on the body 

 of the preceding whorl and the other two occur on the columella. 

 The posterior one of the columellar plaits is the stronger and on 

 either side of it there is a deep columellar sulcus. The genus is 

 probably near Pyramidella, but the umbilicus of that genus is typi- 

 cally imperforate. The genus Creonella is proposed for a group 

 represented by two species from Coon Creek which are unlike any 

 known species of this family in either the Upper Cretaceous or the 

 early Tertiary. A representative of the genus Oheliscus^^ which 

 occurs at Coon Creek and also in the Monmouth of New Jersey, has 

 a single columellar plait, otherwise, in simple, slender, conical forms 

 of the inornate shells, the two groups resemble each other very much. 



Creonella triplicata n. sp. PI. XIX, fig. 8. 



Description. — Shell small and slender, in outline a very sharp cone; 

 spire acuminate, angle of spire constant whorls closely appressed, 

 numerous and narrow, seven in the imperfect type; probably almost 

 twice as many in a perfect form; sculpture absent except for pro- 

 tractive incrementals of irregular strength and spacing that scar 

 the glazed external surface; suture distinctly impressed; body very 

 abruptly constricted in front of the periphery; peripheral angle well 

 rounded; aperture narrow, outer lip broken away; inner surface of 

 labrum corrugated within, with about half a dozen prominent lirse, 

 subequal, closely and evenly spaced ; columella marked by two strong 

 transverse folds behind which and on the body is another fold, the 

 posterior of the columellar plaits is the strongest of these three 

 plaits, on either side of the strong columellar fold are two deep spiral 

 sulci around the columella. 



Dimensions (imperfect individual). — Altitude 14.4 mm.; maximum 

 diameter 3.3 mm. 



This species is well characterized by its narrow, numerous whorls 

 and its very sharp, strongly impressed suture. The species is known 

 from only two specimens neither of which is perfect, but sufficiently 

 preserved to show all characteristic features. 



••" 0?>(/isc«s canellm Whitfield, 1892, Mo7i. U. S. Geol. Surveij, Vol. XVIII' 

 p. 151, PL 19, fig. 1. 



