426 THE OPISTHOBRANL'HIATE 



LoMANOTUS PoRTLANDicus, Thompson. Ann. Mag. Nat. Hist., 3id ser., v, 1860, 



pp. 48—51, 



— Hancocki, Norman. Ann. Mag. Nat. Hist., 4th ser., xx, 1877, 



p. 518 ; 6th ser., 1890, pp. 80, 81. 



— Genei, Ver. Bcrgh, Verh. Zool.-Bot. Ges. Wien, xx.\ii, 1882, 



pp. 66, 67. 



— VAEIANS, Garstang. Journ. Mar. Biol. Assoc, New Ser., I, ii, 



1889, pp. 185—189. 



— EisiGii, Trinchese. J. V. Cams, Prodr. Faun. Mediterr., II, i, 1889, 



p. 207. 



In my previous Report three specimens of Lomanotus dredged in 

 June last year were externally described, and the inference was 

 drawn that the specimens previously obtained on the English coasts 

 (although originally described as possessing specific differences from 

 one another), together with our three specimens, really were members 

 of one and the same species ; and I proposed to give this species a 

 new name, L. varians, though in this proposal, as Dr. Norman points 

 out in his recent Revision, and as others have mentioned to me, I 

 was breaking a recognised " law of nomenclature.^^ Dr. Norman, 

 however, admits the probability of my conclusions except as regards 

 L. Hancocki, which he holds to be distinct. Bergh,^ on the other 

 hand, brackets together L. jlavidus, Portlandicus, Hancocki, and 

 varians, leaving L. genei and tnarmoratus distinct, by which, how- 

 ever, he may have wished to indicate rather his views upon the 

 degree of affinity between the " species " than his agreement upon 

 the question of their unity. 



What seemed to myself to be a remarkable thing on the supposi- 

 tion of there being but one English species was the fact recorded in 

 my original account (1. c, p. 187) of two individuals, whose length 

 did not exceed half an inch, bearing " pieces of spawn." The form 

 of the spawn was certainly unusual, but as nothing was known about 

 the spawning of Lomanotus there was no valid a priori objection to 

 the view that this spawn was deposited by themselves. I was un- 

 willing at the time to dissect the specimens or otherwise alter their 

 appearance, but I have since found that the egg-strings belonged 

 not to the Lomanotus, but to a remarkable parasitic Copepod, pro- 

 bably a species of Splanchnotrophus, which was buried in the viscera 

 of the molluscs, its egg-sacs only being protruded. 



Thus the possible physiological objection to the unity of the 

 British species, viz. that two specimens had been stated to deposit 

 eggs at an unusually early age — when only one fifth of the extreme 

 size — cannot be now urged ; and the question remains to be 

 settled upon morphological grounds only. 



On August 21st of this year I had the good fortune to meet with 



^ Bergh, Die cladohepatischen Nudibranchien, Zool. Jahrbiich., Abth. f. Systematik, 

 Bd. V, 1890, p. 50. 



