WEBB: ON THE GENUS MAEI^LLA. 151 



in the "Land and Fresh-water Mollusca of India," though the 

 genitalia of Girasia Radha, G.-A., are figured, and it is stated that 

 those of G. Mookeri are, with certain restrictions, in every way 

 similar to those of Austenia gigas. The anatomy of Maricella, as made 

 out in Mr. Collett's specimens, agrees with that of Dekhania, so far 

 as indicated by Godwin- Austen. 



It now remains to give revised descriptions of the genus Maricella 

 and its two valid species M. Bussumieri and M. Beddomei^ with some 

 account of their anatomy. 



MARI^LLA, Gray. 



Maricella, Gray: Cat. Pulmonata Brit. Mus., pt. i (1885), p. 62. 

 Tennentia, Humbert: Kev. & Mag. ZooL, 1862, p. 427, pi. 

 Vega, Westerlund : Yega Exped., vol. iv (1887), p. 188, pi. ii. 

 D&khania, Godwin- Austen : Land and Fresh-water Mollusca of India, 

 pt. vi (April, 1888), p. 242, pis. Ivii and Ixii. 



Animal limaciforme, antice convexum, crassum, semicylindricum ; 

 postice post medium angustum, valde compressum, dorso acute 

 carinatum, ad finem pedis peroblique truncatum (ti'uncatura superne 

 verticali, deinde valde declivi) et giandula mucosa terminatum. 

 Pallium ovatum, plus minusve tricarinatum, antice, liberum, postice, 

 in loculamento pedis subquadrato depressum et ad medium per- 

 foratum ; super carinam unam cicatrix a foramine parvo, ad scissuram 

 in margine dextro currit ubi orificium respirationis ponitur : margo 

 posterior scissurae sub aliam productus. Pes canaliculo angusto et 

 lineolis fuscis notatus. Solea obscure tripartita, orificium genitale 

 commune post tentaculum dextrum positum. 



Cochlea interna, subovata, superne convexa et cute protecta, 

 inferne vel concava vel calce completa et convexa; apex posterior, 

 in margine dextro et desuper versus. 



Viscera in pedem post pallium non producta. Maxilla simplex, ia 

 medio elevata. Dens centralis et dentes radulse laterales plus minusve 

 tricuspidati, dentes marginales psene seque bicuspidati. Genitalia — 

 sacculus spiculi amoris prsesens, oviductus liber, turgidus. Penis 

 acute flexus ubi appendix retractorem portans emergit ; epiphallus in 

 flagellum breve productus. 



This slug (PI. IX, Pigs. 1-1 «) is characterized by having a more 

 or less oval mantle, which is free and capable of some amount of 

 extension in front and which covers the viscera behind. The posterior 

 end of this mantle is tucked into a pocket (which has a somewhat 

 square termination) beneath the keel on the hinder portion of 

 the foot. The 'tail' is also laterally compressed, truncated, and 

 bears a slit-like mucous gland at its extremity. Three keels are 

 at some stage more or less strongly developed on the surface of 

 the mantle, and a special feature is the tiny hole in the mantle wall 

 in the middle line posteriorly, while a scar runs from this orifice 



