138 THE NAUTILUS. 



whorl, which is not shouldered as in that species, and in the decided 

 angle at the junction of the columella with the basal lip. The bright 

 honey-yellow color is eminently characteristic. It resembles young 

 specimens of S. crassus, but differs in the particulars stated in con- 

 nection with that species. 



Somatogyrus ohhtsns n. sp. PI. v, fig. 10. 



Shell small, globular, narrowly umbilicate, greenish white, smooth, 

 shining. vSpire very short, apex obtuse. Whorls 3^, those of the 

 spire convex and slightly shouldered, separated by a well impressed 

 suture, body whorl large, globosely convex. Aperture subcircular, 

 rounded above, obtusely angulate below. Lip simple, meeting the 

 body whorl at nearly right angles at its insertion on the parietal 

 wall, expanded below and somewhat thickened within along the 

 basal margin. Columella concave, narrowly reflected : columellar 

 callus not very heavy, and rounded; parietal wall covered with a 

 thin transparent callus. Umbilicus distinct, narrow, somewhat con- 

 tracted by the reflected columellar lip. Alt. 3, diam. 3 mm. 



Coosa river, just above the railroad bridge at Farmer, Ala. 



Only eight examples of this distinct, little form were obtained, but 

 they are very uniform, varying only in size. S. ohtusiis differs from 

 nearly all the Coosa river forms in the narrow, rounded columellar 

 callus and distinct umbilicus. In this respect it is allied to the 

 species of the Tennessee and Ohio drainage, grouping around S. 

 integer, but differs from them all in the obtuse apex, globular form 

 and the decided angle at the junction of the columella with the basal 

 lip. 

 Somatogyrus crassus n. sp. PI. v, figs. 11 and 12. 



Shell small, globose, very solid, imperforate, light greenish yellow, 

 smooth, lines of growth very fine. Spire short, apex obtuse. 

 Whorls about 4, those of the spire slightly convex, suture well im- 

 pressed. Body whorl large, somewhat gibbous and swollen above. 

 Aperture large, rounded above, somewhat flattened basally and ob- 

 tusely angled at the junction of the lip with the columella. Lip 

 simple, thickened within, by a deposit of callus. Columella con- 

 cave, with a heavy, flat callus which extends from one extremity to 

 the lip of the other, and entirely covers the umbilicus. Alt. (apex 

 eroded) 4.25, diam. 4.25 mm. 



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

 above Wetumpka. 



