152 



of the superior antennae, terminal edge narrowly rounded at the tip; post- 

 antennal corner nearly right-angled. First pair of coxal plates gradually 

 widening below, distal edge obtusely truncated, with about 7 strong plumose 

 setae; each of the 2 succeeding pairs with from 5 to G similar setae; 4th pair 

 more than twice as broad as the preceding pair, and bearing on the distal edge 

 a series of about 10 setse ; 5th pair reaching to about the middle of the posterior 

 expansion of the preceding pair, inferior corner bearing 4 curved setae. Last 

 pair of epimeral plates of metasome drawn out to a very long and sharp 

 spiniform projection. Superior antennae nearly as long as the cephalon, 1st 

 joint of the peduncle very large, considerably longer than the other 2 com- 

 bined, and bearing at the inferior corner 3 large auditory bristles; flagellum 

 but slightly exceeding half the length of the peduncle, and composed of G 

 articulations ; accessory appendage somewhat shorter and 5-articulate. Inferior 

 antennae with the penultimate joint of the peduncle heart-shaped and bearing 

 posteriorly 7 strong plumose setae and 5 curved spines, flagellum about the 

 length of the 2 outer joints of the peduncle and 5-articulate. (Inathopoda 

 nearly equal-sized, hands in both pairs oval, with the palmar edge shorter 

 than the hind margin. Penultimate pair of pereiopoda rather strong, scarcely 

 exceeding half the length of the body; last pair with the basal joint rather 

 large, posterior expansion reaching to the end of the meral joint, edge exhi- 

 biting a few, about 5, indistinct serrations, the 2 lower separated by a distinct 

 excavation. Last pair of uropoda very short, only slightly reaching beyond 

 the preceding pair, inner ramus longer than the basal joint of the outer, 

 mucroniform and quite naked; outer ramus with 3 spines exteriorly, terminal 

 joint spiniform, and exceeding half the length of the basal one. Lobes of 

 telson obtusely rounded at the tip. Length of adult female 7 mm. 



Remarks. - Through the kindness of Dr. Hansen, I have had an 

 opportunity of examining the type specimens of Kroyers Plioxus plumosiif< from 

 Greenland, and find them exactly agreeing with the form here described, some 

 specimens of which are preserved in our University Museum, and were examined 

 by Boeck. There cannot therefore be any doubt that this is the true Kroyerian 

 species. The form described by Stimpson as Plwxus fusiform is is most probably 

 the same species. It is the type of the genus. 



Occurrence. I have not myself met with this species off the coast 

 of Norway, and as tbe locality of the above mentioned specimens in our 

 University Museum, is not stated, it would seem to be questionable, whether 

 this species at all can be referred to the fauna of Norway. The form generally 

 recorded by other authors as H. plumosa is evidently not that species, but the 

 following one, and Boeck himself most probably confounded both, though he 



