AMPHIPODA. CHILTON. 43 



TRYPHOSA SARSI, (Bonnier). 

 Tryphosa sarsi, Stebbing, 1906, p. 70. 

 Tryphosa camelus, Stebbing, 1910, p. 574, pi. xlvii. a. 

 Tryphosa nana, Sars, 1891, p. 76, pi. 27, Fig-. 1. 



Locality. Bay of Fires, Tasmania, 10 fathoms. Many 

 specimens. 3 mm. long ; deep salmon coloured ; eyes reddish. 



I think these specimens must be referred to Stebbing's 

 species, the type of which was obtained by H.M.O.S. 



'Thetis" off the coast of New South Wales,' 54 to 59 

 fathoms. In some respects, however, they differ from 

 Stebbing's description and approach still more nearly to 

 T. sarsi. Bonnier, as described and figured by Sars under 

 the name T. nana (1891, p. 76, pi. 27, fig. 1), and in my 

 opinion Stebbing's name must be considered a synonym. 

 The depression on the fourth segment of the pleon is not 

 quite so narrow and deep as that shown in Stebbing's 

 figure, but in some specimens at least it is well marked, 

 while the posterior part of the segment is distinctly keeled. 

 The variation in this character is sufficient to make one 

 doubt its importance as a specific distinction. Stebbing 

 states that in the second antenna the antepenultimate joint 

 of the peduncle is, "contrary to custom, longer than the 

 penultimate.'' This, however, is not the case in the 



'Endeavour" specimens, in which it is either shorter than, 

 or equal to, the penultimate joint. The second gnathopod 

 has the hinder angle of the hand not so acutely produced 

 as shown in Stebbing's fig-ure, but more like that figured 

 by Sars for T. tarsi; the finger again is hardly "small and 

 weak" as described by Stebbing-, but agrees with the figure 

 and description given by Sars, who speaks of it as being 

 ''rather strong." The peraeopods agree with Stebbing's 

 description in having the basal joint large in comparison 

 with the rest of the limb and the merus ("fourth joint") 

 more expanded than is shown in Sars' figures. Stebbing 

 describes the lobes of the telson as bearing three lateral 

 spines instead of two as in T. sarsi. In some of my speci- 

 mens, however, there are certainly only two lateral spines 

 and, as stated below, there may be three lateral spines in 

 T. sarsi. 



I have compai'ed the "Endeavour" specimens with speci- 

 mens sent to me years ago by M. Chevreux from Le Croisic, 



