of British Mollusca. 469 



free and unconnected by membrane dorsally with the head ; 

 Jins more or less ovate, situated nearly centrally on the sides ; 

 arms rather short, their suckers in two or four rows ; tentacles 

 with angular or rounded stalks, tlieir apices slightly expanded, 

 with very numerous small suckers ; gladius small, narrow. 

 Radula with seven teeth in each transverse row, teeth unicus- 

 pidate, with smooth edges, formula 2 — 1 . 1 . 1 — 2. Male 

 with some of the suckers of second and third arms much 

 larger than usual and more pedunculated ; one or both of the 

 first (dorsal) arms more or less hectocotylized. 



4. Rossia macrosoma (delle Chiaje), Gerv. & van Ben. 



Sejnola macrosoma, delle Chiaje, Mem. stor. anini. (1829), pi. lxxi. 



(fide Gerv. and van Ben.). 

 Sepiola macrosoma, Gerv. et van Ben. Bull. Acad. Sci. Bruxelles, 1839, 



p. 39, pi. vi. 

 Rossia macrosoma, d'Orb. Ceph. Ace"t. 1839, p. 245, Sepioles, pi. iv. 



tigs. 13-24. 

 Rossia Oicenii, Ball, Proc. Roy. Irish Acad. ii. (1842), p. 193, J. 

 Rossia Jacobi, id. ibid. p. 193, $ . 



Rossia Oicenii, Loven, GSfvers. k. Vetensk.-Akad. Forhand. 1845, p. 121. 

 Rossia Owenii, Forbes and Hanley, Hist. Brit. Moll. 1853, iv. p. 223, 



pi. SSS. fig. 1, tJ. 

 Rossia macrosoma, iid. ibid. p. 222, pi. MMM. fig. 1. 

 Russia macrosoma, Jeffreys, B. 0. iv. 1869, p. 133, pi. vi. fig. 1. 

 Rossicc Panceri, Tari>.-Tozz. Cep. Mus. Firenze, 1869, p. 46, pi. vii. 



fig; 7, J- 



Russia Oweni, Hovle, Report ' Challenger ' Ceph. 1886, p. 114, pi. xv. 

 figs. 1-9. 



In the c Challenger ' Report Mr. Hoyle doubtfully regarded 

 R. macrosoma and R. Oweni as specifically distinct, and gave 

 five characters in which he then thought they differed. We 

 have now examined together the larger series of specimens in 

 our joint collections, and I have his authority for stating that 

 he no longer regards the first four points as tenable, though 

 he is disposed to consider the fifth, namely that the tentacular 

 suckers (on the margin of the club) are larger in R. Oweni 

 than in R. macrosoma, as sufficient to separate the species. 

 Now I grant that this seems to hold good when British and 

 Mediterranean examples are actually compared ; but the diffe- 

 rence of size is very slight and only relates to the suckers near 

 the base of the tentacular club, and I cannot think that such 

 a slight variation is of sufficient importance to retain even a 

 varietal name, much less specific. Some amount of variation 

 must be allowed. Almost any Mediterranean shell can be 

 distinguished by the practised eye from examples of the same 

 species from our own seas ; and in many cases if mixed lots 

 of a shell were placed before me collected in the restricted 



