1901.] NATURAL SCIENCES OF PHILADELPHIA. 637 



(rates nearly or quite as deeply as the spiral lamella. The sub- 

 columellar lamella emerges to the lip-edge, is bounded by grooves, 

 and there is sometimes some weak crenation of the lip below it. 

 The principal plica approaches the lip, and is about one whorl 

 long. The narrow, straight lunella stands in a ventro-lateral 

 position, and is connected above and below with short but higher 

 upper and lower palatal plicae (fig. 46). . 



Length 16, diam. nearly 3, length of aperture 3 mm. 



Length 15, diam. 3, length of aperture 3.2 mm. 



The clausilium (fig. 43) resembles that of C. oxycyma ; the 

 palatal edge being a little swollen in the middle. The distal end 

 is oblique and strongly thickened, as usual. 



Akasaka, Province Mino, Japan. Types No. 82,273 Coll. 

 A. N. S. P., from No. 748 of Mr. Hirase's collection. 



This Tyrannopkcedusa stands between C. aurantiaca Bttg. and C. 

 iotaptyx Pils. It is more slender than either, and differs from 

 them in the shape of the spire and the relatively smaller aperture. 



Compared wilh C. aurantiaca var. hypoptyehia Pils., the present 

 species is seen to differ in the straighter lateral outlines and larger 

 apex. 



Section STEREOPH^EDUSA Bttg. 



This section comprises four groups of species: The group of C. 

 valida, restricted to the middle Riukiu Islands; 1 the group of 0. 

 japonica, known from Nippon and Shikoku; the group of C. 

 brevior, now known from Nippon, Kiushiu and the Riukiu Islands, 

 and the group of C. entospira, containing a single species from 

 Tane-ga-shima. 



The group of C. japonica includes the following large species : 

 1. C. japonica Crosse. Synonyms of the typical form are 0. 

 kobensis Smith and C. nipponensis Kobelt. There cannot 

 be much doubt that C. eurystoma v. Mart, is a pathologic 

 individual of the same. 



A var. pallens has been distinguished by von Mollendorff, 

 and I have defined var. interplicata. There remain several 

 other more or less well-marked races, which it seems to me 

 inadvisable to name until their distribution can be more fully 

 studied. In Idzumo Province a large, dark race occurs, which 



1 Theee Proceedings for 1901, Vol. LIII, p. 410. 



