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caudal stylets situated close together; they are very small, and each of them is provided 
with a pair of fairly long sete. 
MALE. Unknown. 
OVISACS. They resemble those of the former species. The ovisac represented 
in fig. 2c is 17mm. long and 14mm. broad. In one female were found eleven ovisacs. 
LARVA. Specimens which are full-grown though they have been pulled out of an 
ovisac, resemble those of the former species to such a degree that I have not been able to 
find a single distinguishing mark which appeared to me valid. 
POST-LARVAL DEVELOPMENT. Unknown. 
HABITAT. The branchial cavity of Hippolyte polaris (Sab.) and Hipp. Gaimardii 
M.-Edw. from the Kara Sea. My material from this locality is as follows: in a female 
without eggs of Hipp. polaris appeared beneath a large swelling on the left side of the 
carapace, the above-mentioned gigantic specimen. In an adult male of Hipp. Gaimardi occurred 
under a swelling on the right side of the carapace: a female (represented in fig. 2a) and 
eleven ovisacs (containing eggs, Nauwpli and fully developed larvee respectively); besides an 
adult male and a much smaller, exceedingly young female of Gyge Hippolytes (Kr.); the 
two foremost gills of the host, pertaining to the trunk-legs, had disappeared, the three hind- 
most ones were well preserved; under the apparently sound left-hand side of the carapace 
of the host, one male Gyge was discovered. In another somewhat smaller male of Hipp. 
Gaimardii occurred in the front part of the left branchial cavity three rather small females, 
placed obliquely in a longitudinal row, in the right branchial cavity five similar females, 
three of them far to the front. All the parasites were of sub-equal size and about 1°6 to 
17mm. in length; the gills were somewhat crumpled, and the carapace showed small cavities 
on its inner side in the parts which covered most of the parasites, though its outside did 
not as yet show any real swellings. No Hpicaridea were discovered. 
This species has been found besides at the West-coast of Greenland: in the Karajak- 
Fjord, district Umanak (on ab. lat. 70?/3° N.), by Dr. E. Vanhotfen. This naturalist having 
informed me in a letter that he had found Choniostoma, I asked him to lend me his material, 
and he kindly placed it at my disposal, as well as his own particulars about it. He pos- 
sessed in all four females; two of these belonged to Ch. Hansenii, he had found them free 
in a bow-net, and he writes about them: »... . die ich lose fand, und die aus Krebsen 
stammen miissen, welche in meiner Reuse sich hiuteten oder verzehrt wurden«; about the 
others he writes: »Ein drittes Exemplar wurde in H. Gaimardii...., em viertes in H. po- 
laris.... gefunden«; one of these was Ch. Hansenii, but the other was »zur Hiilfte aut- 
geschnitten«, so that I could not determine it, and I do not know in what species 
of host the specimen had been found. So at least three of the four parasites per- 
tained to this species, moreover, it seems very probable that it lives in both species of 
Hippolyte. 
