1901.] NATURAL SCIENCES OF PHILADELPHIA. 413 



All of the species of this section are new, and from the two 

 islands Okinawa and Oshiuia. 

 Clausilia callistochila n. sp. PI. XXII, figs. 1, 2, 3. 



Shell thick and strong, pale brown, or green from adhering algse, 

 rimate, turreted, the upper third of the length attenuated, with 

 slightly concave outlines, the lower two-thirds rather swollen, the 

 penultimate whorl widest, the last half of the last whorl contracted, 

 compressed laterally. The apex is obtuse. Whorls 11, the early 

 ones worn smooth, the rest closely rib-striate, the riblets on the last 

 whorl coarser and more widely spaced, somewhat undulating and ir- 

 regular. Aperture vertical, rhombic-piriform, with distinct sinulus, 

 the peristome expanded and reflexed, thick, white, the left margin 

 wide and thick as far up as the sinulus, where it is abruptly exca- 

 vated; right margin, from the superior lamella to the base, deeply cut 

 into rounded entering wrinkles, which deeply crenulate the lip-edge. 

 Superior lamella subvertical, rather thick, emerging to the margin, 

 continuous with the high, long and strongly developed spiral 

 lamella. Inferior lamella subhorizontal, strongly approaching the 

 superior lamella within, heavy, not reaching the lip-margin, very 

 strongly spiral inside. Subcolumellar lamella emerging to the lip- 

 edge, where it forms one of the series of lip-folds. Principal plica 

 strong and nearly a whorl long, reaching nearly to the lip ; extend- 

 ing inward far beyond the lunella. Upper palatal plica long, con- 

 verging inwardly toward the principal plica ; lunella short and very 

 obliquely running inward, arising below from a very strong and 

 high, angularly bent, long, lower palaial plica. 



Clausilium (PI. XXII, fig. 4) broad, irregularly curved, 

 abruptly truncate below, slightly thickened along the palatal mar- 

 gin, the apical end of the columellar margin much thickened, bent 

 nearly at a right angle with the rest of the surface, producing a 

 blunt tooth or lobe. 



Length 24, diarn. 5|, longest axis of aperture 5f- mm. 



Length 22J, diam. 5|, longest axis of aperture 6 mm. 



Province Kunchan, Okinawa (Mr. Y. Hirase, No. 634). 



An extraordinary species, not only by the interpalatal lamellae 

 which deeply crenulate the lip, but also by the long and high lower 

 palatal fold and very oblique lunella; the two united in such 

 fashion as to make the figure of an almost prostrate letter A, 

 reminding one of the lunella of some of the C. platydera group of 



