OARBONIPEROUS AGE. 47 



(sp.), as figured by Koninck, on pi. 37 of his work on the Carboniferous Fossils of 

 Belgium. It is considerably smaller, however, has one or two whorls less, and 

 proportionally larger, and less numerous revolving lines below the shoulder ; while 

 those above are smaller in proportion to the breadth of the flattened upper side. 

 It is also related to P. subsinuata, of Meek & Worthen (Proc. Acad. Nat. Sci. 

 Phila. Oct. 1860), but has a more elevated spire, while the upper side of its whorls 

 are more distinctly flattened, and shouldered. 



Locality and position. — Grasshopper Creek, Northeastern Kansas. Coal Mea- 

 sures! (Type 1002.) 



Pleurotomaria snbturbinata. 



(Plate I, Fig. 13.) 

 Pleurotomaria subturbinata, Meek & Hatden, Proceed. Acad. Nat. Sci. Phila. Dec. 1858, 264. 



Shell small, comparatively thick, obliquely conical ; spire moderately elevated, rather pointed at the apex. 

 Volutions six to six and a half, convex, and angular in the middle, obliquely concave above, and having around 

 the middle of the last, just below the angle, a rather narrow, shallow, revolving sulcus. Umbilical region a little 

 depressed, and perforated by a very small pit ; aperture suborbicular. Surface ornamented by small revolving 

 lines (only preserved on the under and outer sides of the body whorl, in our specimen, which is somewhat worn 

 and shows no lines of growth). Angle on the middle of the whorls apparently double, or composed of two 

 parallel lines. 



Length, 0.36 inch; breadth, 0.29 inch ; spiral angle regular, divergence 69°. 



We have seen no specimens of this species with the lip in a condition to show 

 the nature and position of the sinus ; nor are the Hues of growth sufficiently well 

 preserved to indicate the position of the spiral band. It is probable, however, 

 from the appearance of the specimens, that the band is coincident with the sulcus 

 below the angle on the middle of the body whorl. 



Locality and position same as last. (Type 1003.) 



