93 



75. Danielssenia robusta, G. O. Sars, n. sp. 



(PI. LXIV). 



Specific Characters. Female. Body comparatively robust, with the 

 anterior division rather dilated and evenly vaulted above. Cephalic segment 

 nearly as long as the 3 succeeding segments combined, and produced in front 

 to a thin rostral plate obtusely rounded and somewhat defexed at the end. 

 Epimeral plates of the 3 succeeding segments somewhat produced behind. 

 Last trunkal segment very small. Urosome comparatively short, scarcely 

 attaining half the length of the anterior division, and only very slightly tapered 

 behind, its segments minutely denticulate at the hind edges; genital segment 

 about the length of the 2 succeeding segments combined; last segment some- 

 what smaller than the preceding one. Caudal rami very short, being scarcely 

 half as long as they are broad; apical setae rather slender. Anterior antennae, 

 as in the type species, only composed of 4 joints, and exhibiting a very 

 similar structure and armature. Posterior antennae likewise very similar. Man- 

 dibular palp with the basal part considerably expanded, and carrying along 

 the hind edge of the projecting inner part 4 strong ciliated setae. Maxillae 

 and maxillepeds scarcely differing in their structure from these parts in the 

 other species. Natatory legs likewise built on the same type, though differing 

 in the inner ramtis being somewhat more produced. Last pair of legs com- 

 paratively of smaller size than in the other 2 Norwegian species, with the 

 distal joint less broad and having the innermost seta spiniform; inner expansion 

 of proximal joint far less produced, scarcely extending beyond the distal joint, 

 and only provided with 3 marginal setae. 



Colour whitish grey, with a fainte rosy tinge. 



Length of adult female about 1 mm. 



Remarks. The present form is nearly allied to the other 2 Norwegian 

 species, through more robust in shape, and also of larger size than any of 

 them. The structure of the several appendages agrees on the wole rather 

 closely with that found in the said species, except the last pair of legs, which 

 are of much smaller size and also conspicuously different in shape. 



Occurrence. Several specimens of this large species, most of them of 

 the female sex, were found at Ris0r in depths ranging form 30 to 60 fathoms, 

 coarse muddy sand. 



14 - Crustacea. 



