92 



the proximal joint only very slightly expanded inside, but carrying the 3 usual 

 marginal setae; distal joint rather slender, resembling in form that in 2. furcata. 



Body of a whitish colour, without any distinct pigmentary ornament. 



Length of adult female 0.78 mm. 



Remarks. This new species is nearly allied to I. furcata, but is of much 

 smaller size and more slender form of body. In the relative length of the joints 

 of the anterior antennae, it somewhat resembles I. cnsifera; but the structure of 

 the 1st and last pairs of legs is rather different. 



Occurrence. I have found this form in considerable abundance in some 

 localities on the west coast of Norway, for instance at Her0, Kopervik and Buk- 

 ken, and occasionally also off the Finmark coast. It is a sublittoral form, gener- 

 ally occurring near the shores in campany with 1. furcata, ovigerous females of 

 both species being at once distinguished by their very different size. 



56. Idya longieornis, Scott. 



(PI. LIV, fig. 1). 



Idya longieornis, Tli. Scott, in Ann. & Mag. of Nat. Hist, ser. 6, Vol. XV, p. 461, PI. XVII, 



figs. 1017. 



Specific Characters. Female. Form of body rather slender, with the 

 anterior division, seen dorsally, oval fusiform in outline, epimeral plates com- 

 paratively broad, subcontiguous, except the last pair. Urosome about half the 

 length of the anterior division and rather narrow, only slightly tapering distally. 

 Caudal rami short, apical setae, however, much elongated. Anterior antennae ex- 

 ceedingly slender and attenuated, with the 3rd and 4th joints unusually narrow 

 and elongated, both being of about equal length, and somewhat exceeding that of 

 the 2nd joint; terminal part extremely narrow, and scarcely longer than the 4th 

 joint. First pair of legs of inconsiderable size in proportion to the body, and 

 somewhat resembling in structure those in I. furcata, the outer ramus extending 

 considerably beyond the 1st joint of the inner. Last pair of legs with the prox- 

 imal joint only very slightly expanded inside, the innermost of the marginal setae 

 comparatively short ; distal joint very narrow, linear in form, being nearly 6 times 

 as long as it is broad. 



Body of a whitish colour, with a slight bluish green tinge, and exhibiting 

 at the posterior part of the cephalic segment a short transverse band of a dark 

 violaceous hue, and another similar band across the middle of the urosome; an- 

 terior antennae with a small patch of the same colour near the end. 



Length of adult female 1.50 mm. 



