236 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



■with, strongly built bases. The innermost and two or three outermost 

 are smaller, but not denticulate or degraded. The other internal 

 organs appear to be as usual in the genus. The verge is long (11 mm.) 

 and greenish. 



The references given above contain practically no information about 

 H. Adamsii, except that aiforded by the figures, which represent 

 a rather elongated animal having blotches and dots on the back, and 

 dots round the foot, much as described above. The original was 

 probably a specimen resembling the present one. 



The so-called species of Hexahranchus are of very doubtful validity, 

 and are perhaps merely colour varieties. The present specimen shows 

 no variation in structiu'e from the ordinary type, but the pattern of 

 blotches with central dots is distinct and remarkable, as is also the 

 extreme narrowness compared to the length. These two characters, 

 if found in other individuals, constitute a better species than most of 

 those described. 



Aechidoris "Wellingtonensis (Abraham). 



Boris Wellingtone)isis, Abraham: Proc. Zool. Soc, 1877, pp. 211, 259, 

 pi. xxix, figs. 27-28. 



On p. 1121 of his "System der Nudibranchiaten Gasteropoden " 

 (Semper's Reisen, Heft xviii, 1892) Bergh gives, in his list of the 

 species of Boridopsis, " 40. B. lacera (Cuv.), Boris icellingtonensis, 

 Abraham. M. Pacific (Nov. Zel.)." I have not found any explanation 

 of this entry, but an examination of the type-specimen in the British 

 Museum leaves no doubt that Abraham's B. Wellingionensis is not 

 a Boridopsis, but belongs to the Archidorididge. I think also that 

 Cuvier's Boris lacera is not a Boridopsis, but a Rexabranchus. 



This latter view seemed to be adopted by Professor Bergh in 

 treating of Boridopsis in Journ. Mus. Godefi'oy, Heft viii( 1875), p. 85, 

 where he says, " Wenn die Darstellung der Tentakel bei Cuvier 

 richtig ist, gehort diese Form absolut nicht den Doriopsen an." 

 Even in his Syst. Nud. Gast., p. 1091, under Hexahranchus, we 

 find D. lacera, Cuvier, as a synonym of H. Jtammulatus, and in his 

 account of the Opisthobranchiata collected by Schauinsland (p. 225) 

 he adheres to this opinion. Cuvier's Boris lacera (Ann. Mus. Hist, 

 nat., 1804, p. 452, etc.) was brought by M. Peron from La mer des 

 Indes. It would seem to be undoubtedly a Hexahranchus, and not 

 a Boridopsis, on account of the characters presented by the tentacles, 

 the branchiae, and the radula. It is true that Cuvier saj's on p. 459, 

 *' Les Doris difierent eminemment des Tritonies par la bouche en 

 trompe et sans dents dans les premieres, courte at armee de machoires 

 tranchautes dans les secondes." But he says later (p. 460), " Au fond 

 de la trompe est une fente verticale .... derriere est la langue 

 qui ressemble a celle de la Tritonie et de I'Aplysie." AVe have 

 become familiar with the idea that the radula is a set of teeth, but 

 Cuvier evidently thought of it as a tongue, which is equally natural, 

 and when he said that his Boris had no teeth he did not mean that 

 it had no radula. 



