200 VOLUTHARPA. 



and very fragile ; it is large for the size of the embryo, arid is 

 invariably lost in shells which have attained maturity. The 

 remainder of the embryonic shell is translucent purplish red, or 

 wine-color, with revolving lines. I found the embryos on the 

 point of escaping from the ovicapsules in September. The disks 

 of the capsules are three-quarters of an inch in diameter and two- 

 tenths of an inch thick, with the edges perpendicular to the top 

 and bottom, and the angles serrate or furnished with slight 

 coriaceous projecting points.* 



Y. PERRYI, Jay. PI. 19, fig. 389. 



Shell ovately globulose, rather thin, inflated towards the base, 

 spire short, acute, sutures impressed, whorls smooth, color 

 yellowish ash, interior of aperture rusty brown. 



Bay of Yedo, Japan. 



V. AMPULLACEA, Midd. PL 71, figs. 359, 360 ; PL 19, fig. 390. 



Reddish brown under a rufous or yellowish epidermis. 



Length, 22 mill. 



Japan, Sitka ; Sea of Ochotsk, etc. 



Y. DESHAYESIANA, Fischer (fig. 390), is generally considered 

 specifically identical. 



Mr. Dall has described a var. acuminata^ from Sitka ; it has a 

 narrower, less rounded form, with a thicker and stronger, almost 

 pilose epidermis. 



In perfect, fresh specimens of the typical form the thin " epi- 

 dermis is covered with minute, very short cilia, caused by the 

 elevation of minute threads of the epidermis at the intersection 

 of the crowded fine revolving strire which cover the whorl, with 

 the lines of growth. In some apparently perfect specimens, 

 however, the epidermis appears perfectly smooth and even 

 polished. "f 



It is very doubtful whether V. Perryi, Jay, is distinct from this 

 species ; no dimensions are given, but the figure is considerably 

 larger. I do not detect any other difference between them than 

 that of size. 



* W. H. Dall, Am. Jour. Conch., VII, 106. 

 f Dall, Am. Jour. Conch., VII, 104. 



