196 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



superficially described some new species, and then Johnston, 

 Thompson, and Forbes introduced even new genera, but Alder and 

 Hancock, making a special study of this group, found over sixty 

 new species of strange aspect in addition to the already described 

 forms. 



Alder and Hancock were fortunate in impressing the Ray Society 

 with the value of their discoveries, and this Society undertook the 

 publication of the magnificent paintings and drawings in connexion 

 with their monographic account. No more beautiful work has ever 

 appeared, but it has not led to a great deal of interest by British 

 students. On the Continent, however, about the same time, workers 

 investigated and described new forms, and then Bergh, a Danish 

 professor, made a lifelong study of the group, dissecting and minutely 

 describing numerous novelties from all over the world for fifty years. 

 As usual with specialists, he became a very pronounced "splitter", 

 and the new genera projoosed by him, many upon slight anatomical 

 features, are very numerous. 



Sir Charles Eliot, K.C.M.G., recently interested himself in this 

 group, and in 1910 the Ray Society published a Supplementary Part 

 to Alder and Hancock's Monograph, in which Eliot gave a series of 

 notes on the species discovered since Alder and Hancock's time, with 

 some paintings and notes left by these workers. In addition, Eliot 

 gave a Synopsis of Families, Genera, and Species of the British Fauna. 

 This has been used by us in connexion with the Conchological 

 Society's List, and we now give the name we accept, the primary 

 reference, the specific synonyms, and a reference to Alder and 

 Hancock's Monograph, the Conchological Society's List, and 

 Eliot's Synopsis. 



In the present list the name changes are numerous, and the 

 reasons may be here pointed out. Bergh would scarcely recognize 

 any of the older species unless in his opinion he had complete data. 

 Consequently, the majority were left undetermined, though com-' 

 paratively easily recognizable from the characters cited. Eliot was 

 averse to changes even when the facts were clear, and thus the 

 literature of the Nudibranchia is littered with scores of unrecognized 

 names. We have indicated the majority, as we find these molluscs 

 are not difficult to determine when due attention is paid to all the 

 characters of the groups. 



The classification here adopted is mainly that proposed by Bergh. 

 The more important generic name changes may be here summarized: 



AmpJiorina is altered to Cratena. 



Molidiella „ Eolidina. 



Antiopella ,, Janolus. 



Candiella „ Duvaucelia. 



Doris „ Doridigitata. 



Doto ,, Idulia. 



Galvina ,, Euhranchus. 



I 



