30 G Canadian Arctic Expedition, 1913-1918 



(about the length of the seven last abdominal segments); while the claspers of 

 the male A. bungei are more antler than sickle-shaped, and have only one hook 

 (branch) about halfway down the terminal joint, while the small hook-spine on 

 the innerside of ther terminal joint is situated about half way between the 

 large hook mentioned above and the proximal end of the terminal joint, and 

 not at the base of the latter, as in 4 . stefanssoni. The blunt point on the inner- 

 side of the swollen first joint of the claspers also seems to be more in the shape of 

 a spiny protuberance in A. bungei than in A. stefanssoni.'^ 



The length of A. bungei is given for the male, 8-12 mm., and for the female, 

 7-8| mm., but from Daday's figure (fig. 17) it would appear that the ovisac of 

 the females secured has not reached its full development, so this sex probably 

 reaches at least the same size as the male, judging from A. stefanssoni (see p. 

 26, 28). 



I have not been able to consult Sars' (1897, p. 478) original description ' 

 of A. bungei; so all my references to it here are based upon Daday's description 

 and figures (1910, p. 172-75). 



I am indebted to Prof. A. S. Pearse, of Wisconsin University, for telling me 

 that these mature fairy-shrimps from Bernard-harbour represent a new species 

 of Artemiopsis, after he had examined a sample of the specimens sent him. 



My detailed measurements of the size extremes of both sexes follow (alcohol- 

 specimens). Male, 7 mm.; claspers, 2 mm.; head (without A2), 1 mm.; genitaha, 



1 mm. broad and 1 mm. long; abdomen (including genitalia and cercopods), 



2 mm. The same measurements for male 10 mm. long: 2| mm.; IJ mm.; f by 1| 

 mm. ; 2| mm. Female, 8 mm. : Head, 1 mm. ; second pair of antennae, f mm. ; 

 ovisac. If mm. long by 2J mm. broad; abdomen, 2| mm. The same measure- 

 ments for female, 11 mm. long, were: 1§ mm.; 1 mm.; 2 by 3 mm.; 3 mm. 



The shortness of the abdomen (tail) is thus a characteristic feature for both 

 sexes, compared with other fairy-shrimps. 



In colour the males were paler than the females, the former being whitish- 

 yellow with darker (yellow-brown) claspers and foliaceous legs, head, etc. The 

 females had much brighter colours, being orange-red-brown, especially the head, 

 foliaceous legs and the dorsal side; while the tail and ovisac (uterus) is pale 

 transparent, with the eggs coloured olive-brown. Both sexes have the labrum 

 of a strong orange-rose colour. 



Biology 



When found they were, as mentioned above, in lively copulation though 

 there were only a couple of inches of water under the seven inches of thick ice. 

 The females seemed to be a little more numerous than the males, so the latter 

 had a busy time attaching themselves by the aid of their claspers to the dorsal 

 lateral processes of the females (above the ovisac), thus resting on the back of 

 the females. When in copula, the males assist in swimming, though the chief 

 movement is effected by the female. By keeping some of them in a glass of 

 water, I observed that the males would not swim around alone for any length 

 of time, but would quickly "attach" one of the "idle" females in the way just 

 described. During the swimming the females turn the ovisac from side to side, 

 so as to bathe its eggs in the water, in the same way as I have observed in 

 Eubranhipus gelidus (Canadian Field-Naturalist, YehrusiTy, 1921, p. 28); there 

 being, about one second between the turning of the ovisac from left to right, and 

 vice versa. The animals lived in captivity for a few days only and then died; 

 though I kept their eggs until next summer they did not hatch (Rearing No. 98). 



' The peduncles of the composite eyes also seem to be more slender in A . bungei than in A . 

 stefanssoni. 



