THE NAUTILUS. 87 



For comparison with the similar state in S. hinkleyi, a young 

 specimen of 3^ whorls (2^ x 1^ mm.) is also figured. (Fig. 10.) 



The following amended description should be substituted for that 

 originally published for 



SOMATOGYRUS iiiNKLEYi "Walker. PI. vi, figs. 8 and 9. 



Somatogyrus hinkleyi Walker, NAUTILUS, xvii, 135, pi. v, figs. 

 1 and 2. 



Shell globose, conic, narrowly umbilicate when young and perfo- 

 rate when mature ; light horn-colored, smooth, growth-lines scarcely 

 evident. Spire elevated, obtuse; whorls 4-4^, those of the spire 

 convex, body whorl large, more or less shouldered above, but regu- 

 larly rounded at the periphery, suture deeply impressed. 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, acute, in aged 

 examples somewhat thickened within. Columella heavy, callused, 

 flattened and nearly straight, reflected over and nearly concealing 

 the narrow umbilicus, callus thinner on the body wall. 



For better illustration and comparison with S. decipiens I have 

 refigured the original mature type (tig. 8) and have added another 

 of a young shell (fig. 9) of 3-^ whorls (2^x2 mm.) for the purpose 

 of showing the open umbilicus at that stage; the thin, shining shell 

 and rounded whorls are very characteristic. 



S. hinkleyi, when mature, has a larger, thinner shell than decipiens, 

 the columellar callus is not so heavy, and the persistent perforation, 

 very rarely entirely obliteiated, as well as the general shape, are 

 distinctive. 



This species was found by Mr. Smith at the localities mentioned 

 in connection with S. decipiens. 



SOMATOGYRUS HENDERSONI n. sp. PI. vi, fig. 2. 



Shell globose, perforate, thick, solid, greenish-horn-color, smooth, 

 lines of growth slight, but regular. Spire short, subacute, whorls 

 4-4^, flattened above, and roundly shouldered, body-whorl very 

 large, inflated, somewhat constricted immediately below the suture, 

 which is deeply impressed and then flatly expanded and roundly 

 shouldered. Aperture large, subcircular, expanded; lip sharp, cal- 

 lously thickened within, rather abruptly bent in above and meeting 

 the parietal wall at nearly a right angle, broadly rounded below and 



