PARTULA, PELEW ISLANDS. 307 



very thin, white, subhyaline, irregularly subsulculate and 

 sculptured with very dense, somewhat rippled spiral lines. 

 Spire pyramidal, rather acute, suture marked with a white 

 line and substriolate. Whorls 5%, nearly flat, the last a little 

 larger, somewhat ascending in front. Columella deep, slightly 

 arcuate. Aperture oblique, oblong, subcompressed, the mar- 

 gins subparallel; peristome white, thin, equally and broadly 

 expanded. Length 22, diam. 12, aperture 12 mm. long, 4 wide 

 inside. (Semp.). 



Pelew Is.: Pelelu (Dr. C. Semper). 



P. leucotkoe O. SEMP., Journ. de Conchyl. 1865, p. 417, 

 pi. 12, 1 5. 



Differs from P. calypso by the strong obliquity of the 

 aperture, finer sculpture and shape of the shell. 



103. P. CALYPSO O. Semper. PL 38, fig. 2. 



Shell broadly and compressed umbilicate, high-turrited, 

 thin, whitish, roseate towards the apex, longitudinally some- 

 what wrinkled, encircled with wavy spiral lines ; suture some- 

 what thread-like, striolate; spire raised, acute; whorls 6, 

 nearly flat, the last a little longer than the spire, somewhat 

 ascending in front. Columella nearly straight. Aperture 

 slightly oblique, oblong; peristome white, broadly expanded, 

 especially over the umbilicus, the right lip subnodose within. 

 Length 31, diam. 14, aperture with peristome 17 mm. long, 

 5 mm. wide inside (0. Semper). 



Pelew Is.: Pelelu (Dr. C. Semper). 



P. calypso 0. SEMP., Journ. de Conchyl. 1865, p. 418, pi. 

 12, f . 7. 



104. P. THETIS 0. Semper. PI. 38, figs. 3, 4, 5, 6. 



Shell openly and compressed umbilicate, conic-pyramidal, 

 brown, blackish towards the apex, remotely and lightly wrin- 

 kled and encircled with somewhat roughened and beautifully 

 waved spiral lines. Spire conic, the apex pointed but mamil- 

 late. Whorls 5%, a little convex, the suture .somewhat thread- 

 like, striolate; last whorl convex, regularly rounded, some- 

 what ascending in front. Columella somewhat arcuate. 



