208 EULOTA. 



The anatomy is unknown. The group has usually been placed 

 near Trochomorpha, but I am disposed to consider it near Plectotro- 

 pis, partly on account of its hairy keel, partly because Blanford 

 indicates guerini as a species lacking tail-pore. On the other hand, 

 the simplicity of the lip favors the other view. 



E. guerini Pfr., iii, 93. E. tabida Pfr., iii, 94. 



crinigera Bens., iii, 94. 



Section Plectotropis Martens, 1860. 



Plectotropis v. MART., Die HeL, p. 121, type If. elegantissima 

 ffr. Thea ALB., Die HeL, 1850, p. 118, not Thea Mulsant, 1846. 



Shell depressed and carinated, widely umbilicated, dull and 

 brown, with more or less shaggy cuticle and usually a peripheral 

 fringe of hairs; whorls numerous (5 to 8), narrow and slowly in- 

 creasing. Aperture small, angulate-lunar, oblique; lip narrowly 

 expanded, reflexed below. Type elegantissima, pi. 64, figs. 18, 19. 

 (See also pi. 64, figs. 16, 17, E. mackensii, typical form from Okin- 

 awa I., Liukiu group). 



Jaw high-arched, with many (10-19) ribs, more or less denticu- 

 lating the basal margin (PI. 65, fig. 13, E. vulvivaga). 



Radula (pi. 65, fig. 14, E. vulvivaga) having the middle tooth 

 without side cusps, but with a lateral bulging, middle cusps about 

 the length of basal-plate ; laterals with a small ectocone. Margin- 

 als with the long inner cusp bifid, ectocone split into two. The 

 dentition of sumatrana and vulvivaga is practically the same. 



Genitalia (pi. 66, figs. 33, 34, E. vulvivaga) : penis rather long, 

 epiphallus short, strongly bent at the attachment of retractor, con- 

 tinued in a rather short, blunt flagellum. Dart sack large, contain- 

 ing a long, slightly curved dart, lens-shaped in section (fig. 34). 

 Mucus gland inserted high on dart sack, divided into two glandular 

 branches which are wide, flattened and rather incoherent, the dart 

 sack and glands bound loosely to vagina. Duct of spermatheca very 

 long and slender, without diverticulum, bound to oviduct. 



Distribution : Japan, China and adjacent islands, south to Su- 

 matra. 



The anatomy of this group is known by Wiegmann's work on 

 sumatrana and rotatoria, and by my own dissections. E. rotatoria 

 has much the same form of genitalia as I have found in E. vulvivaga, 



