36 AXEL OHLIN, ARCTIC CRUSTACEA. 



1897. llyaracliiui hirticops ideiii, Isopoda, }i. 1.''.7, pl. 00. 

 1897. » denticulata idera, il)m., p. i;>«, jd. 61, fif;. 1. 



During" the expedition of 1898 I dredged this species at 

 the following- stations: 



stat. 33. lat. 78 5()' N., long. 27° 39' E., King Charles Island, dcptli 

 "20 m., bottom tern]». + 0,2 C, sött ycUowish-rcd clay, 

 12 VIII, two spec, 

 » 34. lat. 78 50' N., long. 29° 39' E., King Charles Island, depth 

 60 — 70 m., soft grayish-black clay, 17 \'III, one spec. 

 40. lat. 79 59' N., long." 9° 30' E., 19—20' NW. of Danish Is- 

 land, depth 435 ra., bottom tom]). + I,:-," C, gray clay with 

 stones, 27 VIII, onc spec. 



In all essential points my specimens agree perfectly with 

 Särs' description and fignres, except that the inside of the 

 penultimate joint of the second pair of antennse is armed 

 thronghout with spines, and that the armature along the an- 

 terior margins of the first four segments of the mesosome is 

 more pronounced, and thus, ressembles more that in /. denti- 

 culata as iigured in Särs' Isopoda 1. c. On account of this 

 stronger armature, which seems to be the chief difference be- 

 tween both, I should be inclined to refer my specimens to 

 /. dcnficidata : but, besides the spines on the inside of the 

 fourth joint of the antennse, the geographical distribution does 

 not seem to allow of such a determination. According to 

 Särs, I. hirticeiis seems to be an Arctic form not yet met 

 with south of the Lofoten Islands, but obtained at several 

 stations by the Norwegian North Atlantic Expedition, in 

 depths from 146 to 1333 fathoms, and at three places on the 

 West coast of Greenland (Hansen). 



Ilyarachna denticulata is found by Särs on the West 

 coast of Norway, from Stavanger to tlie Trondhjem Fjord, in 

 depths ranging from some 200 to 800 m. Farther north Särs 

 did not find it, on which account he regards it as a more 

 Southern form. 



I am, therefore, convinced of the specific identity of both 

 forms as shown above in the list of synonymy. In this oj)i- 

 nion I have been eonfirmed after a reference with Dr. H. J. 

 Hansen, of Copenhagen, who also cannot find any differences 

 of importance between both forms. 



Length (of greatest specimen) 8 mm. 



Breadth 3 » 



