93 



Remark*. This is one of the larger species of 2<lya, the length being 

 recorded by Scott as even reaching 1.70 rnm. The Norwegian specimens are not 

 quite as large, but otherwise agree perfectly with the description given by that 

 author. The species is especially characterised by the peculiar appearance of the 

 anterior antennae in the female, these appendages being quite unusually slender, 

 and particularly distinguished by the great length and narrowness of the 3rd and 

 4th joints. 



Occurrence. I took this form, many years ago, at Christiansund and 

 Sauesund, close to the shore among algae; and even at that time I recognized it 

 as a distinct species, to which the provisional name /. nobilis was given. It seems 

 to be rather local in its occurrence, as no specimens have been found in the 

 large material collected during recent years in other parts of the coast. 



Distribution. Scottish coast (Scott). 



57. Idya elegantula, G. 0. Sars, n. sp. 



(PL LIV, fig. 2). 



Specific Characters. Female. Body moderately slender, with the anterior 

 division, seen dorsally, oval in outline, being only slightly narrowed behind. Cephalic 

 segment very large, considerably exceeding in length that of all the free segments 

 of metasome combined, and gradually tapering in front to an obtuse point. Epi- 

 meral plates closely contiguous, and rounded at the tips. Urosome about half the 

 length of the anterior division, and slightly attenuated distally, with the genital 

 segment imperfectly divided in the middle. Caudal rami somewhat more produced 

 than in the 4 preceding species, but otherwise of a very similar appearance. 

 Anterior antennas very slender, resembling in structure those in /. longicornis, 

 but with the 3rd joint comparatively more elongated, exceeding in length 

 both the preceding and succeeding joints. First pair of legs with both rami 

 unusually slender, the inner one being, as usual, the longer, and having the 2nd 

 joint much longer than the 1st and greatly attenuated distally; apical spines of 

 outer ramus more slender than in any of the 4 preceding species. Last pair of 

 legs with the distal joint much elongated, sublinear in form, one of the marginal 

 setae placed at rather a long distance from the others. Ovisac containing only a 

 very limited number of comparatively large ova. 



Body of a pale yellow colour, with several interrupted transverse bands 

 of a clear chestnut brown across both the anterior and posterior divisions. 



Length of adult female 0.80 mm. 



