28 G. 0. SARS. CRUSTACEA. [norw. pol. exp. 



The urosome is scarcely half as long as the metasome, and exhibits 

 dorsally, at the base of the 1st segment, a well-marked saddle-hke depression. 



The eyes (see figs. 1 & 2) are clearly distinguishable, though their pigment, 

 which originally has undoubtedly been of a light red colour, has become 

 absorbed in the specimens by the action of the alcohol. They are of 

 moderate size, and irregularly oval in form, being somewhat contracted in 

 their upper part. The visual elements seem to be normally developed. 



The antennae, as in the other species of this genus, have the flagella 

 more produced than is usually the case in the present familj^ They are 

 rather more slender in the male than in the female [conf. figs. 1 and 2); but 

 the relative length of both pairs is approximately the same in the two sexes, 

 the inferior one being a little longer than the superior. In the male, the 

 latter (see figs, 1, 3) are about the length of the whole mesosome, and have 

 the peduncle very thick and massive, with the 2 outer joints, as usual, very 

 short. The flagellum is composed of numerous articulations, amounting to 

 about 50 in all, the ist being very large and tumid, and clothed inside with 

 numerous sensory hairs, arranged in 2 sets. The succeeding articulations 

 each carry at the hind edge a well developed calceola of exactly the same 

 structure as those on the inferior antennae (figs. 6, 7). The accessory appen- 

 dage exceeds half the length of the peduncle, and is composed of 5 articul- 

 ations, the 1st being much the largest. 



The inferior antennae (fig. 4) have the basal joint globular and wholly 

 exposed {conf. fig. 2). Of the 4 remainings joints of the peduncle, the 

 penultimate is the largest, and is clothed on both edges with short bristles. 

 The flagellum in the male is extremely slender and fully 3 times as long as 

 the peduncle, being composed of about 60 articulations, which are provided 

 anteriorly with well developed calceolae, arranged alternately (see fig. 5). 

 When viewed under a high magnifying power, each calceola (see figs. 6, 7) 

 is found to consist of a short peduncle carrying at the end an oboval, 

 shghtly concave sucking disc, which extends somewhat obliquely and termi- 

 nates in a very thin and hyaline, spatulate rim. 



In the female, as above stated, both pairs of antennae (see fig. 2) are 

 somewhat shorter, and no trace of calceolae is found on the flagella, which, 

 moreover, are composed of a smaller number of articulations. 



