338 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.41. 



are marked by fine, incised, spiral lines between the keels, which are 

 best developed on the well-rounded shoulder, between the summit of 

 the whorls and the strong keel below it. Base of the last whorl 

 shghtly protracted, well rounded, marked by two broad, depressed, 

 spiral cords, of which the basal one, which is a httle anterior to the 

 middle, is the broader. In addition to these there are numerous, 

 exceedingly fine, spiral striations. The axial sculpture of the entire 

 spire and base consists of very fine, incremental lines only. Aperture 

 very broadly ovate, almost circular; peritreme continuous; outer lip 

 thick within, beveled at the margin to form a sharp edge, which is 

 rendered slightly sinuous by the external spiral sculpture; inner lip 

 strong and strongly curved; parietal wall of the aperture appressed 

 to the preceding whorl. 



The type (Cat. 208445, U.S.N.M.) was collected by Dr. Fred Baker 

 at Port Graham, Alaska; it measures: Length 1.4 mm., diameter 

 1.2 mm. 



ALVANIA ALBOLIRATA Carpenter. 

 Plate 29, fig. 6. 

 Rissoa albolirata Carpenter, Ann. Mag. Nat. Hist., ser. 3, vol. 13, 1864, p. 76. 



Shell elongate-conic, rather thick, yellowish white. Nuclear 

 whorls two and one-half, well-rounded, smooth. Post-nuclear whorls 

 marked by low, rounded, subequal, spiral keels, excepting the one at 

 the summit, which is considerably wider than the rest. Of these 

 keels, 6 occur upon the first, 9 upon the second, and 12 upon the 

 penultimate turn. Summit of the whorls appressed. Sutures very 

 poorly defined. Periphery of the last whorl well rounded. Base 

 somewhat produced, well roimded, marked by 9 subequal and sub- 

 equally spaced, spiral cords. In addition to the above sculpture, 

 the entire surface of the spire and base is marked by exceedingly 

 fine, incremental lines which are best seen on the spaces between the 

 spiral keels. Aperture decidedly oblique, broadly oval; outer lip 

 decidedly expanded anteriorly, reenforced with a thick callus; inner 

 lip very oblique, slightly reflected over and appressed to the base; 

 parietal wall covered with a thick callus. 



The type (Cat. No. 16216, U.S.N.M.) comes from Cape San Lucas, 

 Lower California. It has four post-nuclear whorls and measures: 

 Length 3 mm., diameter 1.3 mm. 



ALVANIA LIRATA Carpenter. 



Plate 29, fig. 3. 

 ? Rissoa lirata Carpenter, Cat. Maz. Shells, 1856, p. 358. 



Shell elongate-ovate; early whorls light brown, later ones milk 

 white. Nuclear whorls two, small, well rounded, smooth. Post- 

 nuclear whorls marked by feebly developed, broad, axial ribs, of 



