230 AMERICAN JOURNAL 



pidly increasing, well rounded; suture well impressed; spire 

 moderate, apex acute; aperture widely ear-shaped, columella 

 thickened, flattened, appressed to the body whorl, and covering 

 entirely the umbilicus, strongly folded, and indented above; 

 texture of shell quite solid; light horn color. 



Dimensions. — Length 9 millimetres, diameter 6 mill.; length 

 of aperture 6 mill,, width 3 mill. 



HaUtat. — Elysia, Ohio. A. D. Brown. 



My Cabinet. 



Observations. — There is no American species with which this 

 is likely to be confounded, being unusually solid for the genus 

 and for its size. It was sent to me as L. ccqjerata, Say, which 

 it certainly is not. The columellar fold is much more strongly 

 developed in this species than any others of the catascopium 

 group. 



ANCYLUS. 



1. Ancylus altus, Tryon. — t. 22, f. 15. 



Descn2ytion. — Shell somewhat oblong, broadly rounded at 

 one end, more narrowly so at the other ; convexly much ele- 

 vated, apex obtuse, subcentral ; texture delicate, surface rather 

 smooth. 



Dimensions. — Length 8 millimetres, breadth 6 mill., height 

 4 mill. 



HaUtat. — Klamath Eiver. W. M. Grabb. 



My Cabinet. Cabinet of Mr. Gabb. 



Observations. — This shell is larger, narrower, more elevated, 

 and not so solid as Prof. Haldeman's A. crassus, and it does 

 not approach in outline to either of Mr. Lea's new West Coast 

 species, both of them being more narrowly elongate. It is one 

 of our largest species. 



2. Ancylus subkotundatus, Tryon. — t. 22, f. 14. 



Description. — Shell large, very fragile, oval, nearly round; 

 convex, but little elevated; apex obtuse, nearly central. 



Dimensio7is. — Length 8 millimetres, breadth 6| mill., height 

 3 mill. 

 Habitat. — Umpqua River, Oregon. W. M. Gabb. 

 My Cabinet. Cabinet of Mr. Gabb. 



Observations. — This species, in being large and flat, resembles 

 A. patelloides, Lea, but that shell is much longer, with sides 

 more flattened. I received several specimens, of which the 

 largest is figured. 



