90 



53. Idya minor, Scott. 



(PI. LII, fig. 2). 

 Idya minor, Th. Scott, in Annals of Scottish Nat. Hist. 1896, p. 228, PI. IV, tigs. 1117. 



Specific Characters. Female. Form of body on the whole considerably 

 shorter and stouter than in I. furcata, with the anterior division only very slightly 

 contracted behind, and the epimeral plates more closely contiguous. Urosome 

 about half the length of the anterior division, and of nearly uniform width through- 

 out. Caudal rami very short, with the apical setae less elongated than in the 

 other species. Anterior antennae comparatively shorter than in 1. furcata, with 

 the 2nd and 3rd joints of about equal length. First pair of legs with the outer 

 ramus scarcely extending beyond the 1st joint of the inner; 2nd joint of the 

 latter comparatively longer and more attenuated than in /. furcata. Last pair 

 of legs with the inner expansion of the proximal joint narrowly rounded at the 

 tip. the outermost of the 3 marginal setae considerably longer than the innermost; 

 distal joint subspatulate in form, gradually widening towards the end. 



Colour whitish. 



Length of adult female 0.57 mm. 



Remarks. This is the smallest of the Norwegian species of Idya, and 

 thus fully deserves the name given to it by Th. Scott. The size of the Norwe- 

 gian specimens is even inferior to that recorded by Scott, which gives the length 

 of the animal as 0.70 mm. It is, moreover, easily distinguished from Idya 

 furcata by the much shorter and more compact form of body, in which respect 

 it somewhat resembles the above-described Machairopus minutus. 



Occurrence. I have found this form occasionally in several places on the 

 west coast of Norway in comparatively shallow water, on a muddy bottom. 



Distribution. Scottish coast -(Scott), Franz Josef Land (same author). 



54. Idya ensifera (Fischer). 



(PI. LIII, fig. 1). 



TJiisbe ensifera, Seb. Fischer in Abhandl. d. K. Bayer. Akad. Vol. VIII, p. 668, PI. Ill, 



figs. 6770. 



Specific Characters. Female. General form of body about as in I. fur- 

 cata. Urosome, however, comparatively more slender, exceeding half the length 

 of the anterior division. Caudal rami very short, apical setae, on the other hand 

 much elongated, the outermost and innermost ones being much longer than in 

 I. furcata. Anterior antennae likewise more elongated than in that species, and 



