460 University of Kansas Geological Survey. 



they are even subspinulose. All the specimens of this species 

 in the collection are more or less broken, but judging from 

 their apical angle as indicated by their sides, the largest must 

 have been about five and a half cm. long, and its last whorl 

 about thirteen mm. in diameter." 



The claim of this species to recognition as a Kansas form is 

 based upon a very poorly preserved specimen collected from a 

 thin stratum of sandstone underlying the Fort Benton Lime- 

 stone group. 



Pyropsis coloradoensis Stanton. Plate c, figs. 6-8. 



Pyropsis coloradoensis Stanton, 1892, Bull. U. S. Geol. Surv. No. 106, p. 

 154, pi. xxxn, ff. 6-8. 



Original description : " Shell of rather large size, pyriform, 

 consisting of four or five rapidly increasing volutions ; spire in 

 some specimens much depressed, in others rather prominent; 

 suture distinct, bordered below by a revolving ridge that gives 

 it a channeled appearance ; whorls bicarinate around the 

 middle ; the upper carina the stronger ; obliquely flattened 

 above and rather abruptly contracted below into the canal, 

 which is moderately long and slightly curved. On the whorls 

 of the spire only the upper slope above the greater carina is 

 exposed. In addition to the carinte that are prominent and 

 more or less nodose on the body whorl, the surface ornamenta- 

 tion consists of numerous strong, granular, revolving lines, 

 usually alternating with finer ones and crossed by distinct lines 

 of growth. Aperture elongate ovate, suddenly narrowed and 

 slightly produced above to form a short posterior canal, and 

 more gradually contracted below into a rather broad anterior 

 canal. Outer lip thin and slightly dentate within ; inner lip 

 comparatively thin, forming-a broad, thin glaze on the body 

 whorl above, but thickening and narrowing below until it is 

 free from the columella, leaving a distinct and deep umbilicus. 

 There is a single oblique fold on the columella. Length of one of 

 the types, seventy-seven mm. ; greatest breath, forty-nine mm." 



This species occurs in the Septaria horizon of the Fort Ben- 

 ton formation. 



