1903.] FROM EAST AFRICA AND ZANZIBAR. 363 



whei'eas in A. africana it is violet, both externally and in the 

 intestines; (2) the tentacles are small; (3) there are no tubercles 

 on the underside of the mantle-edge ; (4) the rhinophores and 

 their pockets are somewhat diffeient from those of A . africana ; 

 (5) so are the teeth. 



It is possible that this is the Doris rusticana of Alder <k 

 Hancock (" Notes on a Collection of Nudibranchiate MoUusca 

 made in India," Tr. Z. S. iii. p. 120), but in view of their statement 

 " No oral tentacles (?) ; the head with lateral angles ; branchial 

 plumes five," identification is not possible. 



3. Staurodoris depressa, sp. n. 



One specimen fi-om Wasin. No notes as to living animal. 



The alcoholic specimen is 6'3 centimetres long and 4'9 broad. 

 The general shape is broad and flat. The thick and fleshy 

 mantle-brim is 2 centimetres wide, and the foot consequently 

 unusually small compared with the dorsal surface, being only 

 2*7 mm. long and about 8 mm. broad. The colour is a uniform 

 greyish white, with a slight tinge of violet anteriorly and down 

 the middle of the back. The whole upper surface is covered with 

 warts, which are small at the mantle-edge but inci'ease in size 

 towards the centi-e. The top of the larger ones, which measure 

 5 millimetres across, is flat and hard, consisting of a mass of 

 densely-crowded spicules, and is of a somewhat different sliade 

 from the rest and in life possibly distinctly coloured. On the 

 underside of the mantle-edge are numerous small tubercles of 

 glandular appearance. The openings of the rhinophores and 

 branchiae are tuberculate. The latter orifice is indistinctly stellate 

 and also indistinctly bilabiate, but it is not clear what its original 

 shape may have been. Both the branchial and rhinophorial 

 orifices are closed in the alcoholic specimen. The branchije are 

 six in number, but the hindermost pair are deeply bifid so that 

 there appear to be eight. They are mostly bipinnate and rather 

 scanty. The foot is grooved and notched in front. The tentacles 

 are large, distinct, and somewhat flattened, with i-ather uncertain 

 traces of a groove. There is no labial armature. The radula is 

 broad and white, the formula being about 70.0.70X32. The 

 teeth are simply hamate and all of much the same size. On some 

 of the inner ones I was able to see eight or ten very minute 

 denticles on the inside of the hook. This extremely fine serrula- 

 tion is difiicult to detect, but I expect that it is present on all the 

 teeth except the outermost. The stomach is not free, but is 

 enclosed in the liver. The female reproductive organs are armed 

 with small transparent brick-like scales. 



This form . offers analogies to both Hoynoiodoris a.\i^ Artachcea 

 Bergh, particularly the latter, and the thick leathery mantle and 

 large warts also remind one of Asteronotus. On the whole I class 

 it, though very doubtfully, as Staurodoris, mainly because the 

 openings of the rhinophores and branchiae are closed by the 

 surrounding tubercles. 



[11] 



