1913.] NATURAL SCIENCES OF PHILADELPHIA. 27 



and evenly arched, smooth except for a few indistinct radial costae 

 on part of the penultimate whorl and a few very indistinct spiral 

 lines near the periphery. The peripheral carina is very large, 

 separated from the costa below by a wide furrow. In the basal 

 view showing four spiral costse, the one below the keel is subgranu- 

 late near the parietal wall, but smooth near the basal lip. The 

 two costse near the umbilicus are narrower, the growth lines are 

 very indistinct. The umbilicus is wide, angular at the edge and 

 separated from the spiral costae by a broad, smooth area. The 

 aperture is orbicular; peristome subacute, thickened at the termina- 

 tions of three of the spiral ribs; columella concave, narrow; parietal 

 callus moderate. 



Alt. .71, diam. 1.47 mm. 



Locality. — Porto Barrios and Livingston, Guatemala. 



Types in the collection of the Academj^, tray number 76,501, 

 found in mud collected from the anchor of a vessel at both towns. 



This shell differs from Adeorhis beaui Fisch. by having a more 

 depressed spire and unequal spiral costse. It has a wider umbilicus 

 than Teinostoma hondurasensis. Named in honor of Dr. Paul 

 Bartsch, of Washington, D. C. 



Explanation of Plate II. 



Figs. 1, 3. — VitrineUa hemphilli. ^ 



Figs. 2, 7. — Discopsis schu7>ioi. 



Figs. 4, 6 — Omalaxis fimiculus contrada. 



Figs. 5, 10. — Teinostoma schumoi. 



Figs. 8, 12. — Teinostoma hondurasensis. 



Figs 9, 11. — T iinostoma bartschi. 



