CRUSTACEA MALACOSTRACA. III. 



197 



P. hystrix and, besides, two or three processes, while the dorsal surface has considerably more processes 

 than in P. hystrix; furthermore the lateral margins behind the largest pair of processes are not con- 

 cave as in the other species but slightly convex, and the abdomen terminates in a subacute or some- 

 what obtuse end. 



The eyes (fig. 7 a) are larger and more protruding than in P. liystrix. — First antennular joint is 

 broader in proportion to its length, and has a spiniform process on the upper surface. The antennal 

 peduncles (fig. 7 a) differ much from those in the two other species; the two distal processes on second 

 joint are shorter, while a process directed considerably downwards is found at the inner distal angle; 

 third joint is considerably longer than the second, its outer distal angle produced into a somewhat 

 short process, while on its upper surface two processes are distributed towards the outer margin, and 

 two processes are found on the lower side; fourth joint has the end somewhat thickened, rounded and 

 without spines, but along the upper surface towards the outer margin four or five spines are distributed. 

 — No marsupial lamellae at the base of fifth pair of legs. 



Length of females with marsupium 10 to 14 mm. 



Male. Slender; fourth thoracic segment conspicuously longer than the head and the three 

 anterior segments combined. Otherwise it agrees with the female, except in the feature that the number 

 of small spiniform processes not belonging to the normal transverse rows are extremely few. 



Length 87 mm. — Ohlin has recorded 12 mm., but I suppose this to be a misscript in place of 

 10 mm., and that in reality he has noted the length of the female as that of the male, and vice versa. 



Remarks. The absence of fifth pair of marsupial lamellae and the considerable length of 

 fourth thoracic segment are, in my opinion, too unimportant features for creating a new genus for this 

 fine species. 



Occurrence. Not taken by the "Ingolf". It is only known from the northern part of the 

 east coast of Greenland, where it has been taken at five places. 



East Greenland: Estuary of Hurry Inlet: Lat 70° 50' N., 50 fath.; 1 spec, (by the Ilnd Amdr. Exp.) 

 Lat. 72°26' N., Long. io,°35' W., 105 fath. ; 5 spec, (by the Ryder Exp.) 

 Lat. 72°27' N., Long. i9°56' W.,ab. 100 fath.; 1 spec. - 



— Lat. 72°53' N., Long. 20°36' W., 96 fath.; 3 spec. — — 



— Lat. 74°52' N., Long. I7°i6' W., 175 fath.; many spec. (Nathorst Exp., Ohlin). 



Astacilla Cordiner. 



The number of marsupial lamellse has been dealt with above on p. 192. According to our present 

 state of knowledge, the animals from our area must be referred to five species. But three of these 

 species, all known from Norway and described by Sars, are still insufficiently known, as they are 

 closely related, and the material hitherto found was insufficient for the study of the variation. At the 

 species in question some remarks on the characters are made later on. 



