86 MARINE BIOLOGY OF THE SUDANESE RED SHA. 
Reports on the Marine Bronoay of the SuDANESE RED SeA.—XI. Notes 
on a Collection of Nudibranchs from the Red Sea. By Sir CHARLES 
Eurot, K.C.M.G., Vice-Chancellor of the University of Sheffield. 
(Communicated by Prof. W. A. Hurpmay, F.R.S., F.L.8.) 
[Read 18th June, 1908. } 
Tur Nudibranchs here described were collected mostly by Mr. C. Crossland, 
but partly also by Mr. J. G. Logan at Suez and in the neighbourhood of 
Suakim. The collection, though in many respects typical of the Indo-Pacific 
area, presents several points of interest. The large flat forms (Discodoris, 
Platydoris, etc.), which are generally so abundant on these shores, are poorly 
represented, probably because their favourite habitat (the underside of large 
stones on reefs) did not occur in the collecting-grounds. The presence of 
Goniodoris castanea and Lomanotus vermiformis (which may be the young of 
the Mediterranean species L. genet) is very remarkable, and the question 
arises whether they are part of the original fauna of the Red Sea or importa- 
tions through the Suez Canal. Nudibranchs more than most molluses have 
a fondness for adhering to the bottoms of ships and probably make consider- 
able journeys in this way. On the other hand, Thecacera maculata, hot, 
which is recorded from Karachi (Eliot, in Journ. of Conchol. 1905, p. 242), 
is hardly distinguishable from 7h. pennigera, which is only known from the 
British Coast, and the distribution of Lomanotus and Goniodoris may perhaps 
prove to be similar. 
The reappearance of Ohola pacifica, Thorunna furtiva, and Plocamopherus 
ocellatus is also interesting. These curious forms have hitherto been known 
only by the descriptions of scanty alcoholic material or by the brief account 
of Leuckart (1828). 
I have registered seven new species with considerable hesitation. It is 
possible that none of them are really new forms, but the characters of the 
specimens as preserved do not agree with those formulated for any recognized 
species. Lomanotus vermiformis and Pleuroleura glabra are perhaps immature. 
Artachea verrucosa and Peronodoris denticulata are very like Bergh’s 
A. rubida and Peronodoris cancellata, but differ in their dentition. Kentro- 
doris labialis is perhaps identical with Pease’s Doris setosa, but is certainly 
different from the species of Kentrodoris described by Bergh, and does not 
entirely agree with the characters of the genus as formulated by him, since 
it has a labial armature. But it agrees even less with the characters of the 
only alternative genus, Audura, a form with a labiai armature which offers 
some resemblance to Kentrodoris. It therefore seems necessary either to 
create a new genus for its reception, or to refer it to Kentrodoris. I have 
