160 PALEONTOLOGY. 



ing ridges within; aperture obliquely suboval, witli its longer axis ranging 

 downward and outward. (Surface unknown.) 



Heiglit, 0.55 incb; breadth, 1.05 inches. 



The specimens of this shell in the collection are merely casts in a very 

 fine arenaceoiis material. It certainly differs, however, in its much depressed 

 form, from any otherwise similar described species with which I am 

 acquainted. Its umbilicus is quite wide, but diminishes rapidly in breadth 

 within, in consequence of the depressed form of the shell. The under side 

 of the body-volution is prominently and narrowly rounded around the um- 

 bilicus, but not properly angular; at any rate not so in casts. Owing to 

 the form of the body-volution, the aperture has an oblique outward slope. 

 The whorls seem not to be truncated around the uj)per edge, as is often the 

 case in this genus; but a revolving furrow, just above the suture, gives the 

 latter a duplicated or banded appearance, the band forming a flattened bot- 

 tom to the channeled suture. Only faint traces of very oblique lines of 

 growth are seen on the cast. 



Locality and position. — Chalk Creek, at the mouth of the canon, above 

 Coalville, in the whitish Cretaceous sandstone series, Utah. 



APOEEHAIDJi]. 



Genus ANCHURA, Conrad. 



ANCHURA? FUSIFOKMIS, Met'k. 

 Plate 15, figs. 2, 2 a. 



Shell subfusiform; spire conical, rather short; volutions about five, 

 moderately convex, those of the spire smooth and separated by a com- 

 paratively distinct suture; last one subovate, obscurely angular around the 

 middle in young examples, but with angle entirely obsolete in the adult, 

 gradually tapering below into a long, straight, rather stout canal, which has 

 some appearance of being obliquely truncated at the extremity; outer lip, 

 with extension apparently short, simple, and slightly recurved; surface with 

 only obscure lines of growth, excepting near the lip on the body- volution 

 in adult shells, where there are usually a few small, slightly oblique, longi- 

 tudinal costse, that become obsolete before reaching the suture above and a 

 little below the middle of the volution. (Aperture and columella unknown.) 



