1920.] NATURAL SCIENCES OF PHILADELPHIA. 377 



Length 14, diameter 5.3 mm.; aperture 3.5 mm. long; 9 whorls, 

 the tip lost. 



Oahu: Honolulu Harbor and Kahana. 



Epitonium perplexum (Pse.) is the largest Hawaiian species known 

 to me, also the most generally distributed. E. alatum (Sowb.), 

 E. millecostatum (Pse.) and E. decussatum (Pse.) have been taken by 

 Prof. Bryan and Mr. Thaanmii. E. attenuatum and umhilicatum 

 of Pease I have not seen. I have provisionally identified a small 

 specimen from Waimanalo, Oahu, as E. paumotense (Pse.). The 

 curious, solute E. hyalinum (Sowb.) is represented in Kaneohe Bay 

 by specimens agreeing well with those from Luzon in shape, but of 

 smaller size, the largest 8 mm. long, 4 wide, of five whorls after the 

 slender nepionic tip; 8 ribs on the last whorl, 7 points on each rib. 

 This small race may be called E. hyalinum mokuoloense. 



Haplocochlias (Lophocochlias) minutissimus n. sp. 



The very small shell is umbilicate, turbinate, not nacreous, white 

 with a conic brownish spire. The first whorl appears to be smooth; 

 on the second fine radial folds or puckering appears below the suture, 

 becoming coarser on the following whorl. The last whorl has six 

 strong, smooth spiral keels, narrower than the intervals, which are 

 .flat;, and crossed by numerous retractively axial threads, which are 

 much narrower than their intervals. Within the umbilicus two 

 rather small spiral cords are se6n. The aperture is quite oblique, 

 subcircular. The outer lip is strengthened by a rounded external 

 rib or varix a short distance behind the edge. 



Length 1, diameter 0.9 mm.; 43/^ whorls. 



Mokapu Point, Oahu, 4 specimens. 



By the well-developed varix this shell resembles Haplocochlias 

 or Liotia. I have placed it in the former genus with doubt. It 

 differs by the very strong sculptm^e and the open though not wide 

 umbilicus, which may characterize a separate section Lophocochlias. 



This is the smallest Hawaiian sea shell I have seen. 



LEPTOTHYRA.7 



The following species have been reported from the Hawaiian 

 Islands. 

 L. verruca Gld. 



'Perhaps this name should yield place to Anadema A. Ad., but the type of that 

 group is imperfectly known. It is larger than the known Leptothyras. See 

 Man. of Conch. X, p. 255. 



