SCHIZOPODA AND CUMACEA 



now its proximal half depressed and very much broader than before though not fully as broad 

 as in the next stage, and the outer spine is proportionately somewhat shorter than in earlier 

 stages. 



Stage D (fig. 4^ — 4m). — The spécimen drawn measures 7.5 mm. The rostral plate 

 (fig. 4 k) is conspicuously narrower in front than in stage A ; the eyes are well defined. The 

 antennulae are more developed ; the process from the end of first peduncular joint does not 

 reach the end of the third joint ; the inner flagellum is considerably longer than the sum of the 

 two distal joints of the peduncle and somewhat shorter than the outer flagellum ; both flagella 

 are divided into five to seven joints. The antennae still nearly as in the preceding stage ; the 

 exopod a little shorter and broader than the endopod. The mandibular palp and the endopod 

 of the maxillipeds proportionately a little longer than in stage C. 



The trunk-legs are well developed. The pleopods are well furnished with setse ; their 

 endopod is more than half as long as the exopods, with the secondary articulated lobe developed. 

 Sixth abdominal segment (fig. 4 /) nearly twice as long as broad ; its uropods reach a little 

 beyond the latéral spines of the telson. The telson is between two and a half and two times as 

 long as the sixth segment and a little more than three and a half times as long as broad ; its 

 posterior margin is considerably shorter than in earlier stages and has only five spines which are 

 nearly equal in length (fig. 4 m) ; each postero-lateral margin is somewhat longer than before, its 

 outer spine is shaped as in earlier stages but comparatively a good deal shorter, the second 

 spine has preserved its shape and armature, while the inner spine is flattened and very broad 

 in the proximal half, the spine being only a little more than four times as long as broad, and 

 the spinules along the proximal half of its inner margin are lost. 



The following stages are not represented in the collection. I am sure, nevertheless, that 

 the référence of the stages described to E. superba is correct. A view on Sars' figures of this 

 species and especially of the immature spécimen of E. superba established by him as E. antarctica 

 shows that especially in the fifth pair of legs the sum of the three joints beyond the vertical 

 articulation is short in proportion to the sum of the joints before the « knee » ; this proximal 

 part of the posterior legs is in reality longer in E. superba in proportion to céphalothorax than 

 in any other species of the genus, and the last larval stage just described shows the same ; 

 it may be added that the two posterior pairs of legs when directed forwards hâve the vertical 

 articulation just below the eyes as in Sars' figures of E. Murrayi and E. antarctica (both 

 synonyms to E. superba). 



Locality. — Lat. 70 33' S., long. 89 22' W., May 4, 1898, plankton ; many spécimens. 



Laiva of Euphausia sp. 



(PI. II, fiys. I a— i f 



Stage A (figs. 1 a — 1 c). — Length of my single spécimen 6.2 mm. According to the 

 degree of development of telson and uropoda this spécimen agrées with stage C of E. superba, 

 but its antennae and especially its antennulae are much more developed while the fourth and 

 especially the fifth pair of legs are much less developed than in that animal. The carapace has 

 a well developed latéral denticle ; the rostral plate (fig. la) is subtriangular and rounded in front. 



11 R 57 



