358 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



different, the radula is much smaller, and the structure of the branchial 

 pocket is very peculiar. It is hard to say if the appearance of this 

 organ as preserved is natural. It seems best to register the form 

 provisionally as a new species, which may be intermediate between 

 Staurodoris and Ctenodoris. 



ACANTHODOEIS Falklandica, u.sp. PI. XXVIII, Fig. 8. 



One specimen from Manchester Museum. No notes, except a label 

 saying that it forms part of Mr. "Valentine's collection from the 

 Falkland Islands. 



The shape is somewhat triangular or linguiform. The length 25 mm., 

 the maximum breadth 18, the height 13. The animal seems well 

 preserved, except for a rent in the right side which has carried away 

 some of the genitalia. It is plump and soft, yellowish brown in 

 colour, with a pinkish or purplish tint in places owing to the 

 intestines showing through the semi-transparent integuments. The 

 rhinophores and branchise are lighter and more distinctly yellow than 

 the rest of the dorsal surface, the foot yellow, the orifice of the 

 genitalia bright yellow. 



The back is covered with papillae of various sizes, not set very 

 closelj'. They are hyaline, but appear white in some lights. On the 

 under-side of the mantle are vein-like lines produced by spicules seen 

 through the integuments. These spicules are abundant everywhere 

 on the dorsal surface and mantle-margin. They are brownish, 

 irregular and undulated in outline, but always in one piece and never 

 branched. Their surface is often granulate, and they are sometimes 

 jointed. Among them are found numerous roundish granules. 



The rhinophore pockets are bounded by a raised hyaline edge 

 bearing two processes in front and three behind. These processes are 

 not conspicuous as preserved, but are perhaps contracted. The rhino- 

 phores have a long stalk and about 25 perfoliations. The branchial 

 area is not a pocket, and bears papilliE like the rest of the back, from 

 which it is hardly differentiated. The plumes are 7 or 8, two being 

 close together and bipinnate, but as the main axis lies flat and is 

 attached to the back for most of its length they appear simply pinnate 

 in many places. The foot is triangular, pointed behind, and with 

 a rather long tail (8 mm.). The anterior margin is slightly grooved, 

 but not notched. Over the mouth are two flaps which can be 

 described either as an oral veil deeply bilobed or as unusually large 

 strap -like tentacles. But perhaps the bilobation is not natural. The 

 mantle-edge is ample, and bears above the mouth and also above the 

 tail hard brownish accretions, somewhat resembling those of Archidoris 

 fulva except in colour. 



On opening the body the genitalia are seen to be highly developed. 

 The whole of the right side is filled by the large white mucus gland, 

 and the light-yellow follicles of the hermaphrodite gland are plentifully 

 spread over the top and side of the liver, but do not extend far on the 

 under-side. The liver itself is greenish, not bifid behind, and hollowed 

 out on the right-hand side to receive the genitalia. The intestine j 

 issues near its anterior end and turns backwards at once. 



