328 Proceedings of the Royal Physical Society. 



Leachia ellipsoptera (Adams and Keeve), Steenstrup. 



1848. Loligopsis ellipsoptera, Adams and Keeve, " Samarang " Mollusca, p. 2. 



1849. „ „ Gray, B. M. C. Moll., p. 40. 

 1861. Leachia „ Stp., Overblik, p. 80(12), 



1879. Loligopsis ,, Tryon, Man. Conch., vol. L, p. 163. 



1884. Dyctydiopsis ,, Rochebr., Mouogr. Loligopsidse, p. 18 (10). 



Tlie type specimen of this species, discovered during the 

 voyage of the " Samarang," appears to have been lost, but 

 there are five specimens in the Copenhagen Museum, which 

 are beyond all doubt referable to it. The differences between 

 L. cychtra and this form " consist mainly in the form of the 

 fin and the ventral cartilaginous lines. The almost circular, 

 slightly heart-shaped figure which the caudal fins together 

 exhibit in the former, pass into a distinctly transverse oval 

 in the latter. The drawing of L. cychtra, which represents 

 the fins of the greatest breadth in proportion to the length, 

 is that by d'Orbigny in his great work on the Cephalopoda, 

 but even here each fin is longer than broad, while in L. 

 ellipsojptera each fin is considerably broader than long. The 

 cartilaginous lines on the sides of the mantle are described 

 and depicted by Grant and d'Orbigny as ceasing about half- 

 way between the anterior margin of the body and the tin; in 

 our L. ellvpsoptera they reached just over one-third this dis- 

 tance, and they are, too, as above stated, very weak, and their 

 warts not so large, so prominent, or so numerous." ^ 



Dr de Eochebrune has made this the type of a new genus, 

 which, in violation of the ordinary rule for transcribing 

 Greek names, he writes " Dyctydiopsis ; " but I confess that I 

 see no grounds for such a proceeding, nor do I understand 

 where he obtained his description of the tentacles (" courts 

 subquadrangulaires a cupules petites inegalements distribuees 

 sur toute leur longueur "), for Adams neither mentions nor 

 figures them. 



Brock {loc. cit.) comes to the conclusion that L. ellipsoptera 

 is merely a synonym of L. cychtra, basing his opinion upon 



1 " 



Grant's specimen seems, botli from the drawing and the description, to 

 have had these lines much more j)ronounced than d'Orbigny's " — loc. cit., p. 

 S2 (14). 



