TOO 



ii. Euphausia hemigibba n. sp. PI. XIV, figs. 5^ — 5/. 



Stat. 148. August 10. Lat. o°i7'.6S., long. I29°I4'.5E. 1855111. Hensen vertical net, from 

 1000 m. to surface. 8 adult specimens. 



Description. Very closely allied to E. pseudogibba. Frontal plate, rostrum, eyes 



and antennulse completely as in that species, excepting the dorsal keel on third antennular joint, 

 as this keel, seen horizontally from the outer side (fig. 5 a), reaches about the upper angle of 

 the second joint. The dorsal process on third abdominal segment (figs. $b and 5 c) is an acute 

 plate as in E. pseudogibba, but much more oblong-triangular, and conspicuously longer, about 

 half as long as the fourth segment. Sixth abdominal segment, seen from the side (fig. 5Ó), 

 tapers about from the middle, and more behind the lower margin is more flatly rounded than 

 in E. pseudogibba ; the anal spine in both sexes and the relative length of the rami of the 

 uropods and the telson as in last-named species. 



The copulatory organs (figs. $d — 5/) differ from those in E. pseudogibba especially by 

 the shape of the processes on the inner lobe and by the distal part of the median lobe. The 

 terminal process is somewhat similar to that in E. pseudogibba , but the foot is a little shorter 

 and the heel longer than in that species, and the distal third of the process itself is somewhat 

 different, being compressed and distally curved with the apex triangular, and a lateral, slender, 

 a little curved spine originates at the base of this distal third on the lower side. The proximal 

 process reaches rather little beyond the terminal process; its major proximal part is about as 

 in the preceding form, but less curved, while it is suddenly bent a little more at the beginning 

 of the terminal fifth which is shaped as a somewhat broader, very oblong and a little oblique 

 plate, with the major part of its inner margin and the end finely serrated (fig. 5/). The median 

 lobe has its proximal half considerably narrower than in E. pseudogibba and without any terminal 

 margin ; the lateral process, placed on its lower surface at the inner margin, is somewhat slender, 

 curved as a hook and without any dorsal tooth at the middle ; the distal part of the lobe is 

 normal, not firmly chitinized, only a little narrower than the proximal part, oblong, with the 

 end rounded and sometimes with the outer terminal part folded backwards. 



Length 12 — 16.5 mm. (the largest specimen seen is from the Atlantic). 



Remarks. — The differences between this species and E. pseudogibba are pointed out 

 in the description; the differences between it and E. paragibba are given below. It may be 

 added that the feebly curved, at the end spathulate proximal process and the normal, rather broad, 

 unarmed distal part of the median lobe of the copulatory organs afford characters separating 

 E. hemigibba from the three other species of the gibba-vrowp. 



Distribution. - • As far as I know at present as that of E. pseudogibba. 



12. Euphausia paragibba n. sp. PI. XIV, figs. 6a — 6d. 



Stat. 148. August 10. Lat. o°i7'.6S., long. 129 14'.5 E. 1855111. Hensen vertical net, from 

 1000 m. to surface. 3 adult specimens (<ƒ and 9)- 



Description. — Very closely allied to the two preceding species. Frontal plate, 

 rostrum, eyes and antennulae quite as in E. pseudogibba, the only difference being that the 



