164 



Occurrence. I have met with this small species in several places on the 

 south and west coasts of Norway, from the Christiania Fjord at any rate up to 

 the Trondhjem Fjord. It occurs here and there, together with other species of 

 the genus, in moderate depths among alga? and Hydroida. 



Distribution. Bay of Kiel (Giesbrecht), Scottish coast (Scott). 



105. Amphiascus pallidus, G. 0. Sars, n. sp. 



(PI. CV). 



Specific Characters. Female. Body comparatively robust, with the anterior 

 division somewhat broader than the posterior, and slightly depressed. Rostrum 

 rather broad at the base, triangular. Urosome much shorter than the anterior 

 division, and having the segments densely spinulose at the hind edge ventrally 

 and laterally. Caudal rami short, a little broader than they are long, the 2 

 middle apical setae only slightly thickened at the base. Eye not visible in 

 the living animal. Anterior antennae rather slender, 4th joint scarcely longer 

 than 3rd, terminal part exceeding half the length of the proximal, and with 

 none of the setae ciliated. Posterior antennae with the outer ramus scarcely 

 as long as the terminal joint of the inner, middle joint very small and with- 

 out any setae. 1st pair of legs rather strongly built, outer ramus extending 

 beyond the 1st joint of the inner, its middle joint somewhat larger than the other 

 2, and with a well-developed seta inside, last joint armed with 3 spines and 2 

 geniculated setae; 1st joint of inner ramus somewhat exceeding the length of the 

 other 2 combined, last joint more than twice as long as the 2nd, apical claw 

 rather strong. Natatory legs well developed, with the full number of setae. Last 

 pair of legs with the distal joint rounded oval in form, carrying 6 marginal setae, 

 2 of which, attached to the tip, are very narrow and quite smooth; inner expan- 

 sion of proximal joint extending somewhat beyond the middle of the distal joint, 

 and obliquely truncated at the tip, marginal setae 5 in number. Ovisacs of mo- 

 derate size, containing numerous ova. 



Male with the 2nd basal joint of 1st pair of legs produced inside to 2 

 blunt spines, in front of which is a small knob-like prominence. 2nd pair of legs 

 with the spines of the outer ramus much coarser than in female, inner ramus 

 much shorter than the outer and transformed in the usual manner, distal joint 

 considerably dilated in the middle, one of its spiniform appendages being exceed- 

 ingly strong. Last pair of legs much smaller than in female, distal joint rather 



