610 



terminal joint small, simple, setiferuus. Telson imperfectly defined from the 

 last segment, smooth above, and broadly rounded at the tip. 



Hemarlcs. — This genus was established in the year 1845 by Kroyer, 

 to include an arctic species, *S'. tijpicHt<. It is intermediate between Ccrajiiis 

 and CoropMum, resembling the former in the general habitus, but agreeing 

 somewhat more closely with the latter in the structure of the several appen- 

 dages. From both genera it may be readily distinguished by the very much 

 elongated inferior antennae and by the rather different structure of the 

 gnathopoda. The genus comprises as yet only 3 species, 2 of which belong 

 to the fauna of Norway and will he described below. 



2. Siphonoecetes Colletti, Boeck. 



(ri. 218, fig. 1). 



Siphonoecetes Colletti, Boeck, Crust, ampli. bor. & arctica, p. 268. 

 Syn.: Siphouoecetes inucronatus, Metzger. 



Body slender, depressed, nearly linear in form, with the metasome 

 and urosorae very small and combined occupying only Vs of the length of 

 the body. Cephalon produced in front to a short, acutely triangular rostral 

 projection, lateral lobes much produced, and somewhat tumefied at the tip. 

 Coxal plates edged with slender bristles; 1st pair angularly produced in 

 front; the 3 posterior pairs rather broad in proportion to their depth, and 

 having the anterior lobe somewhat larger than the posterior. Ej^es well 

 developed, rounded, with dark pigment. Superior antennae considerably 

 exceeding half the length of the body, and reaching beyond the penultimate 

 peduncular joint of the inferior ones, joints of the pedirncle nearly of equal 

 length, flagellum not attaining half the length of the peduncle, and composed 

 of 7 articulations. Inferior antennae very much elongated, about equalling 

 in length the whole body, tlie last 2 joints of the peduncle neai'ly equal-sized, 

 flagellum much shorter tlian tlie last peduncular joint, and composed of only 

 3 articulations, the last 2 very small. Anterior gnathopoda with the propodos 

 about the length of the carpus, and conically tapering distallj', lower edge 

 armed with 3 strong spines. Posterior gnathojioda rather strongly built, with 

 the basal joint comparatively short and thick, meral joint produced at the 

 end below to an obtuse setiferous prominence, carpus having below a very 

 narrow lobe armed with a strong spine and several slender bristles, propodos 

 large and oval in form, with tlie palm quite short, and the hind margin 



