OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 287 



two-fifths of its length. In the second maxillipeds the last joint reaches beyond the 

 penultimate without making a neatly continuous curve. The second peraeopods 

 reach beyond the scale of the second antennae by the whole length of the sixth joint, 

 which is a little longer than the fifth, as the fifth is than the fourth ; the seventh 

 joint is rather more than half as long as the palm of the sixth. 

 Locality. — St. Vincent, Porto Grande ; Station 24. 



Leander affinis (Milne-Edwards). 



1837. Palemon affinis, Milne-Edwards, Hist. Nat. Crust., vol. ii. p. 391. 



1852. Paleemon affinis, Dana, U.S. Expl. Exp., vol. xiii. p. 584 ; (1855) pi. xxxviii. fig. 5, a-g. 



1888. ,, ,, Bate, Rep. Voy. " Challenger," vol. xxiv. p. 782, pi. cxxviii. fig. 5, a, d, i. 



1888. „ „ Witmer Stone, in Heilprin, Pr. Ac. Sci. Philad., pp. 318, 322. 



1890. Leander affinis, Ortmann, Zool. Jahrb., vol. v. p. 521. 



1893. „ ,, Ortmann, Ergebn. Plankton- Exp., vol. ii., G. b., p. 47. 



1901. Palmmon affinis, Rathbun, U.S. Fish. Coram, for 1900, vol. ii. p. 125. 



1910- Leander squilla, Stebbing, Ann. S. Afr. Mus., vol. vi. part iv. p. 386. 



This species was named for its affinity to Leander squilla, rather inappropriately 

 as it has proved, since the latter species belongs to the group which has the 

 mandibular palp biarticulate, while here it is three-jointed. Moreover, in the first 

 antennae the shortest flagellum has the number of free joints greater than that of 

 the coalesced joints, which is not the case in L. squilla. Bate observes in regard to 

 his Australian specimens, as a remarkable circumstance, " that neither of the flagella 

 of this pair of antennae has attached to it any of the membranous cilia so common in 

 the order." In our specimens the short flagellum is well provided with the usual 

 filaments, but they are short, and might easily escape notice. Dana supplies some 

 good figures of the mouth-organs. But the outermost division of the first maxilla is 

 represented much shorter than it is in our specimens. It is possible that Dana saw 

 it foreshortened. The continuity of curve between the last two joints of the second 

 maxillipeds is well shown in Dana's figure. The terminal joint of the third 

 maxilliped is represented both by Bate and Dana as relatively shorter than it is in 

 our specimens, especially in the larger ones. As to the second peraeopods, Dana gives 

 the " fingers much less than half the length of the hand " ; Miss Rathbun gives " palm 

 1'5 times as long as the fingers"; Bate allows the chela to be "about half the 

 length of the palm " ; his figure, however, is in near agreement with Miss Eathbun's 

 estimate. In a species ranging from Porto Rico to New Zealand some amount of 

 variation may well be expected. Dana describes the apex of the telson by saying 

 " extremity of abdomen very narrow, having three minute spinules, and between 

 them two longish setae." Bate, speaking of the telson, says : " On each side within 

 the margin are three small spinules, and the distal extremity is fringed with a few 

 hairs." In our specimens the telson ends in a spine-like median process, the base of 

 which joins the lateral margins by slightly oblique lines, with a spine at each angle, 

 and between these spines and the median process are two other spines nearly three 



