186 REPORT ON THE NUDIBRANCHIATE 



Reasons drawn from a study of tlie amount of variation wliich is 

 exhibited among Nudibranchs generally bave led me to take tbe 

 latter course, although it is not without some diffidence that I do so. 



The history of the genus in British waters is, so far as I know, as 

 follows : Forty-five years ago Alder dredged a single example near 

 Berry Head^ Torbay, for wliich he created a new genus [Eumenis) 

 and specifically named Eumenis marmorata. At the time he was 

 not aware that Verany had already published the description of a 

 genus which was identical (as Alder and Hancock subsequently 

 stated in their Monograph) and which had been named Lomanotus 

 by him. In Lamlash Bay, Isle of Arran, another example was 

 dredged by him, for which he created a new species, Lomanotus 

 flavidus. In Weymouth Bay, also, Thompson (24) dredged two 

 specimens, one in December, 1855, the other in December, 1856, 

 which agreed apparently in all the points by which they differed 

 from the two previous examples, and for which Thompson (adopting 

 Alder's view) founded a new species which he named portlandicus. 

 Lastly, Dr. Norman (19) dredging off Berry Head, Torbay (the 

 spot whence Alder obtained his first example), in June, 1875, 

 obtained another fine specimen for which he founded the species 

 Lomanotus HancocJci. 



Of the three specimens which we obtained on June 11th two were 

 very closely alike both in size, structure, and colour, and the other 

 was rather larger and much paler in colour and showed certain 

 structural differences. I will describe this one first. In length it 

 was just over five eighths of an inch. It was of a fawn colour, 

 slightly reddish on parts of the back, with numerous small white 

 spots, but without any dark spots or patches. The veil was pro- 

 duced into two tentacular prominences on the right, one on the left. 

 The foot was as usual produced into a curved process at each corner 

 anteriorly, and it was fairly broad as in L. marmoratus and flavidus 

 (and probably in L, portlandicus and L. HancocTci also, since no 

 peculiarity in this respect was noticed). The epipodial ridges 

 formed on each side an almost upright waved expansion undulating 

 into four lobes beset with small papillae of irregular form, the median 

 one in each lobe being somewhat longer than the rest. This condi- 

 tion is almost exactly the same as that described for L. marmoratus, 

 but in our specimen the four inward undulations of the ridge were 

 considerably more conspicuous than the outward from possessing 

 larger papillee, these papillae increasing in size towards the centre of 

 each of the (inwardly-directed) lobes. The waved ridges, indeed, 

 might be said to be broken into four semicircular lobes, whose con- 

 vexities are directed towards the median dorsal line of the animal. 

 (Compare the definition of the species marmoratus, A. and H., in the 



