54 G. 0. SARS. CRUSTACEA. [norw. POL. EXP. 



prominence. On a closer examination, this prominence (see figs. 4, 5) is 

 found to be minutely incised at the tip, terminating in 2 short points, each 

 carrying outside a slender tentacular filament. The cephalic segment is well 

 defined from the 1st pedigerous one, a distinct suture being observable between 

 them. On the other hand, no such line of demarcation is to be detected 

 between the 2 last segments, which accordingly are completely coalesced into a 

 single segment. The lateral parts of this segment are produced behind in the 

 form of rather large triangular lobes projecting on each side of the base of the 

 tail. The latter division is fully half as long as the anterior, and rather slender. 

 It is, as usual, composed of 4 segments; but the last of these, the anal seg- 

 ment, is so very small, that it may easily escape attention. The 1st, or 

 genital segment is somewhat larger than the succeeding one, and is consider- 

 ably dilated in the middle, exhibiting below, moreover, a broadly rounded 

 protuberance. 



The caudal rami (see fig. 10) are pronouncedly lamellar, more than twice 

 as long as they are broad, and gradually somewhat widening distally. They 

 each carry 4 densely plumose setaD, 3 of which issue from the obtusely 

 rounded tip, the 4th somewhat more externally from a distinct ledge of the 

 outer edge. The setae are not of any considerable length, being scarcely more 

 than half as long as the tail. The outermost seta is a little shorter than the 

 other 3, which are equal in length. As in most other Calanoids, moreover, 

 a very delicate, unciliated bristle is seen orginating from the dorsal face of 

 each ramus, near the inner corner, being angularly bent, with the distal part 

 extending outwards across the caudal setae. 



Of any eye, no trace could be detected, though most probably it has 

 been present in the fresh state of the animal. 



The anterior antennae (fig. 6) are rather slender and attenuated, somewhat 

 exceeding the length of the anterior division of the body. They are composed 

 of 24 well-defined articulations, of which, as in the 3 preceding forms, the first 

 2 and the 8th are the largest. The joints are clothed anteriorly with short 

 bristles, more densely crowded together in the proximal part of the antenna. 



The posterior antennae (PL XIII, fig. 1) have the outer ramus very fully 

 developed, and considerably longer than the inner, its structure being about 

 the same as in the 3 preceding forms. 



