467 



slender, the superior ones (in female) considerably exceeding YS of the length 

 of the body, 1st joint of the peduncle scarcely as long as the 2nd, but much 

 thicker, and produced at the end posteriorly to an obtuse denticle, last joint 

 rather small, flagellum somewhat longer than the peduncle, and composed of 

 about 20 articulations. Inferior antennae considerably longer than the superior, 

 and having the last joint of the peduncle very slender and elongated, flagellum 

 about the length of the peduncle. G-nathopoda of a structure similar to those in 

 P. Swammerdami, though somewhat more slender. The 2 anterior pairs of 

 pereiopoda normal; the 3 posterior pairs having the propodal joint much 

 shorter than the carpal one, and the dactjdus in all recurved, basal joint of 

 antepenultimate pair produced at the infero-posteal corner to a very strong, 

 somewhat hook-shaped projection, that of last pair very broad, obcordate in 

 shape, with the infero-posteal corners triangularly produced. Branchial 

 lamellae simple, not lobular. Uropoda and telson nearly as in the 2 preceding 

 species. Body semipellucid, with a yellowish tinge, and having along the 

 back a series of rounded orange-coloured patches, sides of body irregularly 

 streaked and mottled with a similar pigment, which also occurs on the 

 antennae and legs; buccal area and uropoda tinged with a dark chestnut- 

 brown pigment; ova in the marsupial pouch bluish green. Length of adult 

 female 8 mm. 



Remarks. - This form was first described by Sp. Bate in his well- 

 known work on the British sessile-eyed Crustacea as a species of Dexamine. 

 Boeck, however, justly pointed out its difference from that genus, and referred 

 it to the genus Atyliis of Leach. It* is undoubtedly congeneric with the 2 

 preceding species, from which, however, it is at once distinguished by the 

 well-defined dorsal projections of the metasome and last segment of mesosome. 



Occurrence. The species would seem to be a more southern form, 



since it has never been met with in the arctic region of Norway. I have 

 collected it not rarely in several places off the south and west coasts of 

 Norway, as also in the Trondhjemsfjord, in moderate depths ranging from 10 

 to 50 fathoms, 



Distribution. Shetland Isles (Norman), British Isles (Robertson), 

 Kattegat (Meinert), coast of France (Chevreux). 



