THE NAUTILUS. 59 



weak spiral lines. Whorls 6, very slowly increasing, convex, the last 

 slightly deflexed in front, the periphery near the summit, the base 

 very convex. Aperture small, lunate, the peristome narrowly re- 

 flexed and a little thickened, connected across the parietal margin 

 by an elevated white, callous lamella. At its last third the last 

 whorl is obstructed within by a vertical parietal barrier, behind tlie 

 ends of which stand two tubercles, the upper one triangular, the 

 lower one oblong, each giving out a low callous towards the other; 

 and by six palatal plica; : the first minute, subsutural ; the second 

 larger, slightly oblique and curved ; the next three connected, larger 

 and more oblique, and the sixth plica smaller and standing on 

 the umbilical wall. Alt. 3, diam. .5.7 mm.; width of umbilicus 2 

 mm. Miyakojima, Riukiu. Types no. 87637 A. N. S. P., from no. 

 1295 of Mr. Hirase's collection. 



Tills is the first Plectopylis found in the Japanese Empire, and is 

 one of the most interesting of Mr. Hirase's many discoveries. The 

 admirable studies of Mr. Gude enable us to fix its position as nearest 

 the Chinese P. ctUlsculpta MUdff. (see Gude, Science Gossip, iii, 

 180, 181, Dec. 1896, and Mlldflf., Jahrb. D. M. Ges., ix, 1882, p. 

 184, and x, 1883, pi. 12, f. 12). 



A NEW LOWER CALIFORNIAN SONORELLA. 



BY H. A. PILSBRY. 



Sonorella lohril lioderma, n. subsp. 



The shell is similar to Iohrv\ but the last whorl is a little niore 

 convex and evenly rounded, and the last two whorls are glossy, with 

 no granulation, being marked with faint growth-striae only. The 

 spire is sometimes a little more elevated than the type of »S'. lohrii. 



Near Moleje, Lower California, Cotypes no. 58107 and no. 88367 

 A. N. S. P., the latter from Lower California without special locality. 



The type specimen of S. lohrii Gabb is finely granulated through- 

 out. S. I. lioderma would be a species the way some people cut up 

 Sonorella. 



GENERAL NOTES. 



West American Shells. — Professor Keep's new book on the 

 shells of the Pacific coast is now in press, and will be published in a 

 short time. There will be over 300 illustrations. The marine 



