On a New S2ncies of Odojms. 321 



veloped, has a long pointed median process, on either side 

 of which are two denticles. On either side of this tooth is 

 a much smaller one, about one-third as wide, with a single 

 point situated near its outer margin ; and beyond this 

 again is a tooth slightly broader than the median one, 

 with a single denticle near its inner margin. The teeth of 

 the outermost pair are long, slender, and gracefully recurved ; 

 externally to them are placed a series of rectangular plates. 



Of the comparatively few raduhe of the genus Octopus 

 wliich have been figured, the one in question recalls that of 

 0. vulgaris, as delineated by Troschel;* but there the median 

 tooth has only one denticle on either side, while in the next 

 succeeding members of the radula the apex of. the tooth is 

 much nearer their centre. The radula of Odopits Bairdii, 

 Verrill,f has a median tooth with no lateral denticles; 

 but the two medio-lateral series present a considerable 

 resemblance to those of the present species. 



With respect to the affinities of the animal just described 

 but little can be said ; the form which approaches it most 

 nearly seems to be a small species described by Quoy and 

 Gaimardj under the name Octopus lunulatus, but, so far as I 

 can discover, never since observed. 



It was characterised by very definite circular markings, 

 which were of a blue colour, and were in the form of raised 

 rings, with a tubercle in the centre. There were also circular 

 markings on the inner surface of the interbrachial membrane, 

 which are entirely absent- in this specimen. Further, the 

 upper surface of 0. lunulatus is covered with tubercles, whereas 

 the present species has none of these. 



That these differences are not due to the fact that my 

 specimen had been preserved in alcohol may be seen by 

 reference to the description given by d'Orbigny of Quoy and 

 Gaimard's specimen, after it had been similarly preserved.g 



* Ueber die Miindtlieile der Cei^halopoden, Archiv f. Xaturgescli. Jahro-. 

 xix., Bd. i., p. 1, 1853. 



+ The Cephalopods of the north-eastern coast of America, Trans. Connect. 

 Acad., vol. v., pt. 2, pi. xlix., fig. 4. 



t Voyage de I'Astrolabe, Zoologie, t. ii., p. 86, pi. vi,, figs. 1, 2. 



§ Ferussac et d'Orbigny,; Hist, Nat. gen. et part, des Cephalopodes 

 Acetabiiliteres, p. 59. Paris, 1835-48. 



VOL. VII. X 



