THE CRUSTACEA OF LIVERPOOL BAY. 173 
Norman. It appears to me that these are one species, 
agreeing as far as I can see in all respects both with 
Boeck’s description and Kroyer’s figure and description of 
Amphithoe bicuspis in his ‘‘Gronlands Amphipoder.” On 
the other hand there can be little doubt that Mr. Spence 
Bate has erred in referring his Pherusa bicuspis to that 
species. The form of the wrist (carpus) and hand (propodos) 
of both gnathopods, as shown and described both in the 
British Museum Catalogue and the ‘‘ British Sessile Eyed 
Crustacea,” is alone sufficient to show that the species in 
question cannot belong to the genus Pherusa, as limited 
by this author. In Pherusa the wrist of the gnathopods 
is narrow and as long as the hand, while in P. bicuspis it 
is short and produced backward, as shown in the figure.+ 
Moreover Canon A. M. Norman informs me that the name 
of C. bidentatus was originally given in MS. by Mr. Spence 
Bate himself, who must therefore have recognized it as 
distinct from his Pherusa bicuspis. Whether it should be 
referred to Pleustes or Calliopius is amore difficult question. 
It is one of the commonest species in Liverpool Bay, and 
is found at all depths down to 30 fathoms, becoming more 
abundant as the depth increases. It varies much in colour, 
being pure white, freckled with red, or olive green. The 
long upper antenne are generally barred with red. (I, II 
and INT). 
Pleustes bicuspis, Kroyer, ‘“ Gronlands Amphipoder,”’ 
Danske Vid.-Selsk. Afhandlung vill., 1838. 
Paramphithoe bicuspis, Bruzelius, Skand. Amphip. 
Gamm-,, 1859, p. 73. 
Paramphithoe bicuspis, A. Boeck, Crust. Amph. Bor. 
und Arct., 1870. 
+ I have examined the type specimens in the British Museum and find that 
they agree with the figure in the Brit. Sess. Eyed Crust., but not with Kroyer’s 
and Boeck’s figure and descriptions of Amphithoe bicuspis. 
