EXPEDITION ANTARCTIQUE BELGE 



as the fiât spine, is inserted laterally just in front of the latter, while it is absent in the following 

 stage. The trunk-legs of first pair are long (fig. 2 g), much longer than the second pair and 

 proportionately much longer than the corresponding leg in the large spécimen ; in thèse legs 

 the last joint is siightly more than half as long as the penultimate joint. As a parallel it may 

 be mentioned that Holt & Tattersall state that most of their spécimens — ■ from i3 to 28 mm. 

 in length — had the first pair of legs much longer than in the spécimen figured by Sars, while 

 in two spécimens thèse legs are only as long as in the types. 



The two remaining spécimens, which are respectively 7.7 mm. and 6.3 mm., hâve arrived 

 at the same stage of development as the largest spécimen described. In both spécimens the 

 préhensile legs are wanting. 



Localities. — Lat. 70°4i' S., long. go° 14' W., May 1, 1898, plankton VIII; one spéci- 

 men. — Lat. 70°33' S., long. 89° 22' W., May 4, 1898, plankton IX; two spécimens (the types 

 for my figures). — Lat. 70 o5' S., long. 83° 07' AV., August 3i, 1898, plankton ; one spécimen. 



Distribution. — Tins species is evidently widely distributed. Sars enumerates four 

 localities more or less distant from Kerguelen, two places in the Antarctic Océan at the 

 ice-barrier, and a place in the South Atlantic, south of B'uenos-Ayres. Holt & Tattersall 

 had numerous spécimens from the Discovery, they « were taken both in the open sea and 

 through holes in the ice » ; Stebbing mentions it from the Falkland Islands. 



B. — SPECIMENS IN THE LAST LARVAL STAGE (') 

 4. — Euphausia cn'stallorophias Holt & Tatt. 



(PI. I, figs. 3*-3<- 

 1906. Euphausia crystallorophias Holt & Tattersall. Ane. Mag. Nat. Hist., soi. 7, vol. XVII, p. 3. 



Three spécimens are to hand, the largest measuring 10 mm., the two others 9 mm. in 

 length, but ail in the same stage of development. Mr. Holt kindly presented me with several 

 spécimens of his E. crystallorophias, and the smallest of thèse is nearly 14 mm. A comparison 

 with this spécimen gave the resuit that the three spécimens captured by the Belgica belong to 

 the same species. Mr. Holt's young spécimen has not yet lost the spiniform process on the front 

 margin of the basai antennular joint, but the telson has obtained the shape and armature found 

 in adult spécimens. The spécimens from the Belgica hâve the antennular process mentioned at 

 least as long as in Mr. Holt's spécimen, but the telson has a pair of long, slender spines 

 inserted in front of the long, depressed, movable spines (fig. 3 c). The three spécimens agrée 

 with E. crystallorophias in the shape and relative length of the joints in the antennular peduncles, 

 in showing no trace of lappet on the basai antennular joint, in possessing very large eyes 

 (fig. 3 a), in the shape of the rostrum, furthermore in the slenderness of the body, in the 

 existence of a marginal tooth on the carapace, and in the relative length of the rami of the 

 uropoda. 



(1) A single spécimen of Thysanoessa macrura, which ought to hâve been dealt with under this heading, is 

 described above together with a more developed spécimen. 



