112 



as long, posterior incision narrow and not extending to the middle, terminal 

 lobes obtusely truncated at the tip, each with a small apical denticle. Co- 

 lour pale yellowish with a faint reddisli tinge on the anterior division of 

 the body. Length of adult female 13 mm. 



lieniarls. — Owing to a certain resemblance in its outer habitus and 

 especially in the structure of the posterior pereiopoda to Onesinws plaufus (Kroyer) 

 this form was confounded with the latter by Sp. Bate, and even Boeck, in 

 determining the specimens of both forms preserved in our University Museum, 

 has fallen into considerable error, some of the specimens having been labelled 

 by him as Onesinnis pUiitius, whereas specimens of the latter form were vice- 

 versa determined as Menigrates obfusifrons. On a closer examination the 

 present form may, however, easily be destinguished from Onesimus plautus, 

 not only liy its much more tumid body, but also by the considerably coarser 

 structure of the antennte and V)y the \evy diiferent form of the anterior gna- 

 thopoda. 



Occurrence. — 1 have myself only met with this form in 2 localities 

 within the Arctic region of Norway, viz., at Bodo and in Lofoten at depths 

 varying frtim 20 to 5(J fatlioms. Prof. Lilljeborg found it, however, at Grij) 

 outside Christiansund on the West coast of Norway, and Boeck has stated its 

 occurrence also oft the South coast at Mandal. Finally, Mr. Schneider has 

 observed it in the neighbourhood of Tromso. None of these authors, however, 

 would seem to have observed this form in its fully adult state. 



Distribution. — British Isles (Sp. Bate). 



Gen. 2<.t. Lepidepecreum, Sp. Bate, isos. 



Body short and stout, with the back carinated and tlie integuments 

 very tirm, calcareous. Coxal plates large and deep. Superior antennae with 

 tlie joints of the peduncle partly produced anteriorly, accessory appendage 

 very small or quite wanting; in male withtmt any calceolse but provided 

 with dense tufts of sensitive bristles. Inferior antennae in female scarcely 

 as long as the superior and much more slender, with the antepenultimate 

 peduncular joint rather produced; in male very elongate, exceeding the length 

 of the body, flagellum very slender, -filiform and j)rovided with distinct cal- 

 ceolse. Ejnstome fonning a broad compressed plate ])rojecting in front of the 

 anterior lij). Mandildes of moderate size, cutting edge simple, molar expan- 



