THE NAUTILUS. 135 



All the figures are drawn on the same scale so that the relative 

 size of the different species is represented on the plate. 



Somatogyrus hinkleyi n. sp. PI. v, figs. 1 and 2. 



Shell globose-conic, imperforate or with a mere chink at the um- 

 bilicus, light horn-colored, smooth, growth lines scarcely evident. 

 Spire elevated, apex obtuse. Whorls 4-4|^, those of the apex con- 

 vex, penultimate and body whorls more or less shouldered; suture 

 deeply impressed ; body whorl large, convex or in shouldered ex- 

 amples somewhat flattened at the periphery and obtusely angled 

 below. Aperture large, rounded above, somewhat flattened at the 

 base and decidedly angled at the junction of the lip with the base of 

 the columella and angular at the upper insertion of the lip; lip 

 simple, in aged examples somewhat thickened within. Columella 

 heavy, callused, flattened and nearly straight, callus thinner on the 

 parietal wall. Alt. 4|, diam. 3| mm. Alt. o, diam. 3^ mm. 



Coosa river at "Wetumpka, Ala. (type locality), five miles above 

 Wetumpka, Wilsonville and Fort Williams' Shoals. Also Talla- 

 poosa river at Tallassee, Ala. 



This fine species was collected by Mr. Hinkley in considerable 

 numbers at all the localities above mentioned, except at Tallassee, 

 where only a single specimen was found. It occurred " on rocks in 

 swift water, generally on the under side. Sometimes several indi- 

 viduals were found close together." It differs from all the known 

 species in the elevated spire and conical form excepting S. pcnnsyl- 

 vanicus and virginicus herein described, but those species are much 

 smaller and decidedly different in contour. Young shells have the 

 whorls decidedly convex, the slioulder not appearing until after the 

 third w^horl. The penultimate whorl shown in its entirety in half- 

 grown specimens is usually quite quadrate, owing to the shoulder and 

 flattening of the periphery. In mature specimens the shoulder tends 

 to become less evident and often entirely disappears. I take great 

 pleasure in naming this unusual form after its discoverer, Mr. A. A. 

 Hinkley, whose recent trip to the Coosa was so fruitful in novelties. 



Somatogyrus constrictus n. sp. PI. v, fig. .3. 



Shell small, conic, light horn-colored, smooth, except for tlie fine 

 growth lines. Apex eroded in all specimens seen, the portion re- 

 maining consisting only of the last 2-2^ subcylindrical whorls, which 

 are very convex with a deeply-impressed suture, the body whorl is 



