COT.LINGE : ON THE ANATOMY OF THE VITRINA IRRADIANS. 65 



Statement which I can confirm after an examination of a large numljer 

 of specimens in my own collection. 



As Simroth"* has pointed out, the terminology employed by 

 Godwin-Austen for the mantle-lobes is somewhat confusing. I have 

 tried to use it, but find it unsatisfactory. The mantle comes round 

 the shell on all sides, being produced posteriorly on each side into 

 tongue-like extensions, a further and similar extension is present on 

 the right side. 



Ratnadvipia ipradians, Pfr. 



(Pis. V and vi, figs, i — 13.) 



Vifrina if/ridians, Pfeiffer : Proc. Zool. Soc, 1S52, p. 156. 



Ilelicarion irradians, Theobald : Supp. Catal., p. 24. 



liafnadvijiia irradians, Godw.-i\ust. : Moll, of India, 1899, vol. ii, 

 p. 93, pi. Ixxxv, figs. I — Sa. 



Animal steel-grey, the head and dorsum variable, sometimes being 

 almost yellow or even blue. Mantle lobes surround the shell on all 

 sides, posterio-laterally produced into tongue-like extensions. Dorsum 

 sharply keeled. Peripodial groove deep, and well defined. Rugae 

 large. Caudal mucous pore large, but not extending to foot-sole. 

 Foot fringe bluish-grey. Foot-sole yellow, not divided into median 

 and lateral planes. Usually there is a median groove, with oblique 

 lines running from the foot fringe. 



Length (in alcohol) 72 millim., breadth of foot-sole 7-5 millim. 



Shell thin, but not transparent, whorls few, body whorl large, lip 

 produced on the right side. 



i^aZ^.— Kandy, 1500 ft. Ceylon. (O. Collett). 



27ie Alimcntari/ Canal (PL v, fig. i). — -The intestinal tract is 

 thrown into four loops, the third being somewhat short. Posterior to 

 the crop the intestine exhibits three constrictions (Fig. i), a feature 

 constant in all but one of the seven specimens dissected. The 

 stomach is fairly large and completely surrounded by the lobes of the 

 "liver." The remaining parts call for no special mention. 



The Generative Organs (Pis. v and vi, figs. 2 — 11). — Externally 

 the generative orifice leads into a small vestibule into which the 

 dart-sac opens anteriorly, the vngina in the middle, and the penis 

 posteriorly. 



The vagina is a long tube-like duct with its internal walls plicated 

 (Fig. 3, vg.). At its jiosterior end it receives the globular, sessile 



8 Zool. Jahrb. (Abth. f. Syst.), 189S, Bd. xi, pp. 166-167. 



