CRUSTACEA MALACOSTRACA. III. |oe 



< s small (fig. 6 a). First antennular joint oblong without any dorsal process. Antenna: with 

 the peduncles 5-jointed, but the first joint is short and not visible from above; second joint is very 

 thick, nearly as long as the third, with the outer angle produced into a long or very long process, 

 and on the upper surface a distal very long, spiniform process and a more proximal shorter process. 

 Third joint (fig. 6 a) with only a single process, but this is very long and projects from the outer distal 

 angle. Fourth joint is slender, without spines, except that the distal outer angle is produced into a 

 conspicuous, acute tooth. - The marsupial lamellae at fifth pair of legs are easily seen. 



Length 8-9 mm. Male unknown. 



Remarks. That this species is the real A.hyslrix G. O. S. is absolutely certain, while the 

 animals figured by Ohlin as A. hystrix belong to a new species, P.frigidum. - At the front end of 

 the marsupium of one specimen was found a male of the new Kpicarid, A rcturochtres pule Ari/x-s, to be 

 described later on. 



Occurrence. Taken by the "Ingolf" at a single station. 



West of the Fames: StaL 44: LaL 6i42' N -. Long- 93' W., 545 fath., temp. 4-8; 5 spec. 



Furthermore it has been taken by Cand. mag. Ad. Jensen almost south of the Faeroes at LaL 

 6oxo'N n Long. 625'W., 620 fath., temp. -r- 0-15, u spec, and Norman has recorded it from an adja- 

 cent place in the cold area, viz. LaL 6oai' N., Long. 54i' W., 580 fath. 



Distribution. It has been secured somewhat south-west of the last-named place at LaL 

 5954' NT Long. 752' W., 355 fath. (Norman). Sars has recorded it from three places, viz. one some- 

 what more distant from the Fseroes than from Norway at LaL 6244' N., Long. i48' E., 412 fath., temp. 

 4- it>; the second far south-west of Lofoten at LaL 66*4 1' N., Long. 659' E., 350 fath., temp, -j- 0.9, 

 and the third west of Lofoten at LaL 682i' N., Long. io4o' E., 457 fath., temp. -- 07. The other loca- 

 lities recorded in the literature for this species belong to P.frigidum. 



It is an interesting fact that among the seven stations enumerated one belongs decidedly to 

 the warm area and five to the cold area, but looking at the map of the Norwegian North-Atl. Exp. 

 it is seen that all cold stations are in reality near the limits of the cold area, and vice versa. 



137. Pleuroprion Murdoch! BenedicL 



1898. Arcturtts Murdochi Benedict, Proc, BioL Soc. Washington, Vol. XII, p. 49, fig. 9. 

 ! 1905. Plturoprion Richardson, Monograph, p. 342, figs. 371372. 



The single old female seen by me agrees well with Richardson's description in nearly ever)' 

 particular of any significance; Benedict's figure (copied by Richardson) is good excepting as to the 

 proximal part of the abdomen, which does not agree so well with Richardson's ameliorated description. 



The species is closely allied to P. hystrix but differs in the following particulars. Most of the 

 processes on the body are conspicuously shorter than in P. hystrix; an important feature is that my 

 specimen agrees with Richardson's description in having on the dorsal side of first abdominal .segment 

 "two longitudinal rows of three spines in each row, one on either side of the median line"; these pro- 

 cesses are nearly equal in size, and their number and moderate size is an excellent specific character. 

 In the antenna: the three processes on second joint are short; third joint has in my specimen a tcr- 



