140 



different families. I think the genus ought more property to be placed within 



the family Thalestridce as here defined, though in some respects it certainly differs 



conspicuously from the other genera. Off the Norwegian coast occur 4 species 

 referable to tbis genus. 



88. Westwoodia nobilis (Baird). 



(PL LXXXV & LXXXVI). 

 Arpacticus nobilis, Baird, British Entomostraca, p. 214, PL 28, figs. 2, 2 a e. 



Specific Characters. Female. Body very robust, somewhat compressed 

 in front, attenuated behind. Cephalic segment occupying almost half the length 

 of the entire body, and rather deep; dorsal face strongly vaulted, rostral projec- 

 tion triangular, acute at the tip and pointing straight down. Epimeral plates of 

 the 3 succeeding segments of moderate size, deflexed and rounded behind. Last 

 segment of metasome much narrower than the preceding ones. Urosome scarcely 

 more than l / s as long as the anterior division, and gradually tapering behind, 

 genital segment about the length of the 2 succeeding ones combined, and imper- 

 fectly divided in the middle. Caudal rami broader than they are long, and trans- 

 versely truncated at the tip, apical setae rather elongated and divergent. Anterir^ 

 antennae comparatively short and stout, composed of only 5 articulations, 2 of 

 which belong to the terminal part; middle joint much the largest and formed by 

 the fusion of 2 joints. Posterior antennae with the outer ramus shorter than the 

 terminal joint of the inner, 1st joint about the length of the other 2 combined. 

 1st pair of legs with the outer ramus scarcely Vs as long as the inner, and con- 

 sisting of only a single joint, no trace of any subdivision being visible; inner ramus 

 with the seta of 1st joint attached considerably in front of the middle, apical 

 claws finely pectinate on the one edge and rather unequal, the inner one being 

 more than twice as long as the outer. Last pair of legs with the distal joint 

 small and rounded in shape, carrying 5 slender seta?; inner expansion of proximal 

 joint extending as far as the distal joint, and edged with 5 very slender and 

 elongated setae. Ovisac large, pyriform, extending considerably beyond the end 

 of the urosome. 



Male differing only slightly, in its external appearance, from the female 

 Anterior antennae transformed in the usual manner, and consisting of 7 well-de- 

 fined joints, the 2 sensory appendages of moderate length. 1st pair of legs dif- 

 fering from those in female only as regards the spine attached to the inner corner 

 of the 2nd basal joint, which is quite short, tap-shaped, and terminating in an 



