40 THE VOYAGE OF H.M.S. CHALLENGER. 



The uropoda (see fig. 4) are comparatively a little longer than in the preceding species 

 and have the scape cylindrical, with but four denticles along the inner edge. Of the 

 branches, in this species the inner one is the larger and about as long as the scape. 

 Its first joint is scarcely twice as long as the last, slightly tapering, and provided along 

 the inner edge with only five denticles. The last joint is linear and has three denticles 

 along the inner edge and a much stronger one at the tip, besides another very small apical 

 denticle and a simple slender bristle. The outer branch is considerably shorter than the 

 inner and has the last joint provided with a series of ciliated setse along the inner edge. 



Habitat. — The above described specimen was taken from a very considerable depth 

 in the North Pacific, at Station 246, July 2, 1875; lat. 36° 10' N., long. 178° E.; depth, 

 2050 fathoms; Globigerina ooze; bottom temperature, 35°*1. 



Genus 2. Eudorella, Norman, 1866. 



Eudorella Norman, Eep. Brit. Assoc, 1866, p. 197, note. 



Euilora, Sp. Bate, Ann. and Mag. Nat. Hist., ser. 2, vol. xvii. p. 457. 



Generic Characters. — Anterior division of body more or less dilated, almost clavate. 

 Carapace comparatively small, not crested dorsally, truncated in front, without any 

 pseudorostral projection, the lateral lobes ascending perpendicularly and meeting 

 immediately in front of the median lobe, leaving between their extremities an oval 

 orifice for the expulsion of the water. No eye. Five segments of the trunk exposed 

 behind the carapace, rapidly diminishing in height posteriorly. Tail very slender and 

 movable. Antennulae rather large, geniculate, outer part being reflexed and doubled 

 upon the inner by an elbow-like flexure ; inner flagellum well developed, uniarticulate, 

 with three strong apical bristles. Antennae in female very small, uniarticulate. Oral 

 parts and legs nearly as in Lexicon. Telson wanting. Uropoda with both branches 

 biarticulate. 



Remarks. — As regards the structure of the several limbs, this genus exhibits great 

 affinity to the genus Leucon, though it is easily distinguished by the very different form 

 of the carapace, which gives to the species of the present genus quite a peculiar appear- 

 ance. The strong development and peculiar curvature of the antennulas affords another 

 good generic mark. No less than seven different species of this genus have hitherto 

 been distinguished. Of these, three occur in the Northern Ocean, one in the Arctic Sea. 

 two off the eastern coast of North America and two in the Mediterranean, one of which 

 is also found in the Northern Ocean. Besides these, an eighth species, which is 

 described below, was procured during the Challenger Expedition. 



