399 



A Complete List of the Opisthobranchiate MoUusca 

 found at Plymouth; 



WITH FUKTHER OBSERVATIONS ON THEIR MORPHOLOGY, COLOURS, AND 

 NATURAL HISTORY. 



By 



Walter Garstaiig, IVI.A., 



Jesus College, Oxford; Assistant to the Director, M.B.A. 



With Plates XXVII and XXVIII. 



This paper is intended to fui^nisli a complete list of all the species 

 of Opisthobranchiate Mollusca found up to this time by the Marine 

 Biological Association at Plymouth, together with various notes upon 

 their morphology and natural history. The Nudibranchiate section 

 of the group has, however, already formed the subject of a pre- 

 ceding report published in this Journal,^ so that species which have 

 not since been taken are recorded here by their names only, a fuller 

 account of them being given in the previous report. All the species 

 there recorded are distinguished in this paper by asterisks {*) 

 affixed to their names. I have had the advantage of several works 

 upon the classification of the group which have recently appeared, 

 notably Carus's excellent Prodromus Faunae Mediterranese, vol. ii, 

 part 1, 1889 ; Bergh's Die cladohepatischen Nudihranchien (Zoolog. 

 Jahrbiich., v, 1890 ; for a copy of this admirable woi'k I am in- 

 debted to the author) ; and Norman's Revision of British Mollusca 

 (Ann. Mag. Nat. Hist., VI, vol. vi. No. 31, 1890, pp. 60—91). I 

 must also mention Vayssiere's Recherches Zoologiques sur les Mol- 

 lusques Opistohranches du Golfe de Marseille — /. Tectibranches (Ann. 

 Mus. Hist. Nat. Marseille, Zool., II, 1885, Mem. No. 3) as having 

 been of great service; and I regret that up to the time of going to 

 press the second part of M. Vayssiere's work has not arrived at the 

 Laboratory, and I have been unable to refer to it. 



Since my Report on the Nudibranchiata was in type last year 

 Prof. Herdman^ has published several papers upon the value of 



' Garstang, Report on Nudibranchiate Mollusca of Plymouth Sound, Journ. Mar. 

 Biol. Assoc, N. S., vol. i, No. 2, 1889, pp. 173— 198. 



' Herdmaii, On the Structure and Function of the Dorsal rapilla: in Ntidihranchiala, 



