333 



Last pedigerous segment very small. Urosome about 2 /s the length of the anterior 

 division, with the posterior edges of the segments minutely spinulose ventrally and 

 laterally, genital segment rather large and expanded, last segment much shorter 

 than the preceding one, and having the anal opercle very small and smooth. 

 Caudal rami scarcely half as long as they are broad, and transversely truncated 

 at the tip, innermost apical seta twice as long as the outermost, inner medial 

 seta remarkably strong and considerably thickened in its proximal part, being 

 about half the length of the body. Eye apparently present, but very small. 

 Anterior antennae not nearly half the length of the cephalic segment, and gradu- 

 ally tapering distally, 1st and 2nd joints the largest, terminal part exceeding 

 half the length of the proximal one. Posterior antennae with the outer ramus 

 scarcely more than half as long as the distal joint, and carrying 5 setae, 2 on 

 the 1st and 3 on the very small last joint. 1st pair of legs with the outer ramus 

 widening very considerably distally, its last joint being much larger than either of 

 the 2 preceding ones and armed with 4 spines and 2 setae, the spines being fringed, 

 like those on the 2 preceding joints, with slender spinules along the outer edge; 

 inner ramus nearly twice as long as the outer, and straight, 1st joint much the lar- 

 gest, 2nd joint obliquely produced outside, last joint sub-linear and carrying at the, 

 end 2 slender setae and an intermediate ciliated spine. Inner ramus of the 3 suc- 

 ceeding pairs with the middle joint acutely produced at the outer corner, terminal 

 joint carrying on the tip a long spine and 2 comparatively small setae, its inner 

 edge being provided in the 2nd pair with one, in the 3rd pair with 3, and in 

 the 4th pair with 2 setae. Last pair of legs with the distal joint of rounded oval 

 form, and edged with 4 comparatively short setae; inner expansion of proximal 

 joint extending considerably beyond the distal joint and carrying on the narrowly 

 truncated end 2 unequal seta? and inside them a short spine. 



Male unknown. 



Colour not yet ascertained. 



Length of adult female 0.43 mm. 



Remarks. This small Copepod has at first sight a certain resemblance 

 to the species of the genus Idy<m, Philippi, the anterior division being distinctly 

 depressed and sharply marked off from the posterior. The structure of the several 

 appendages, however, is very different, and proves it to belong in reality to the 

 present family. 



Occurrence. Some specimens of this form, all of the female sex, were 

 picked up from a sample taken at Skutesnaes. south-west coast of Norway, from 

 a depth of about 12 fathoms. 



