306 PROCEEDINGS OP THE NATIONAL MUSEUM. vou 55. 



intensely dark green that it appears almost black. The surface of 

 the shell is marked by decidedly retractively slanting incremental 

 lines, and fine incised spiral striations, and rather strong, quite 

 regularly spaced wrinkles which are placed at right angles to the 

 lines of growth and give the surface a decidedly malleated 

 appearance. 



The three specimens yield the following measurements: Number 

 of whorls, 4.6, 4.6, 4.4; altitude, 14, 14.1, 13.3; greater diameter, 22.5, 

 23, 19.7; lesser diameter, 20.3, 19.8, 17.9. The first of the three is 

 registered as Cat. No, 218405, U.S.N.M.; the other two are in Mr. 

 Webb's collection. They were collected at Makabenga. 



LEPTOPOIVIA MAUBANENSE MAKABENGANA, new subspecies. 



Plate 20, figs. 4-6. 



Shell broadly conic, thin, semitranslucent, bluish-white. Nepionic 

 portion of the shell smooth. Postnuclear turns well rounded, marked 

 by decidedly retractively slanting incremental lines and numerous 

 very fine, closely spaced, incised spiral striations, which are present 

 both on the spire and the base. In addition to the above sculpture, 

 four slender, obscure cords divide the space between the summit and 

 the periphery into five subequal areas. The cords are marked at 

 fairly regular intervals by elongate, brownish spots. Periphery of 

 the last whorl marked by an acute compressed keel, which extends 

 quite prominently to the edge of the outer lip. Suture but slightly 

 impressed. Base very short, slightly concave immediately anterior 

 to the peripheral keel, then moderately rounded, very narrowly 

 umbilicated, without color markings. Aperture very oblique; outer 

 and basal lips decidedly expanded and reflected; inner lip strongly 

 curved, slightly reflected, almost covering the umbilicus; parietal 

 wall covered by a thin callus. 



The type (Cat. No. 218406, U.S.N.M.) and a paratype in Mr. 

 Webb's collection come from Makabenga. The type has 6.2 whorls 

 and measures — altitude, 18.8 mm.; greater diameter, 20 mm.; lesser 

 diameter, 15.7 mm. The paratype has 6.4 whorls and measures — 

 altitude, 19.4 mm. ; greater diameter, 20.3 mm. ; lesser diameter, 15.5 

 mm. The present subspecies differs from Leptojyoma maubanense in 

 being of much lighter texture, in having the peripheral keel much 

 more pronounced and extending to the very edge of the lip, the base 

 less rounded, and the umbilicus much narrower. 



EXPLANATION OF PLATES. 

 Plate 18. 

 Fig. 1. Cochlostyla luzonica makahengana, top view, natural size. 



2. Cochlostyla Inzonica makahengana, profile view, natural size. 



3. Cochlostyla luzonica makahengana, basal view, natural size. 



4. Cochlostyla Ugnaria aguinaldoi, natural size. 



5. Cochlostyla carinata lunai, natural size. 



8. Cochlostyla microstoma viscayana. natural size. 



