494 



BULLETIN OF THE BUREAU OF FISHERIES. 



Calliopius lseviusculus (Kroyer). 



Head with a small, triangular rostrum; eyes rather large, reniform; first antenna? somewhat 

 shorter than second, the first basal joint considerably thicker and a little longer than second, third 

 joint with inferior process long and narrow and furnished below with about eight cal jeohe; flagellum 

 a little longer than peduncle, joints very short at base but distally longer than broad and produced at 

 anteroinferior angle; each joint with a pair of calceolse and several olfactory seta' on the lower side 

 ami a few very short seta' above; second antenna' about two-fifths tin' leiutli of body; last two basal 

 joints of subequal length, the penultimate reaching as far as penultimate basal joint of first antennae; 

 flagellum subequal to peduncle, joints not produced below and each furnished with a pair of calceoli 

 on median side; first four coxal plates deeper than broad, about as deep as their segments, and 

 increasing successively in length, the first produced at anterior angle: first two gnatnopods of similar 

 form and of nearly equal size, the second a little the larger, with lobe on posterior side of carpus longer 

 and narrower; hands ovate, palm very oblique with a row of stout spines on outer side which begins 

 a little beyond middle of palm and a little above its distal end; gnathopods of male similar to those of 

 female, but stouter; merits of first two pcra'opods strongly produced downward at anterior angle; 

 merits of three posterior pereeopods strongly produced downward at posterior angle, that of last pair 

 more dilated than in preceding ones; first three abdominal segments more or less protruding at 



v 



L_ 



Calliopius la viusculus. In connection with the antenna*, two of the inure distal segments of the flagellum are shown. 



posterior end, especially in older specimens; posterolateral angles of second and third segments with 

 a small tooth; second, third, and fourth, and often, but to a less extent, the first, segments more 

 or less indented above near base; first uropods with outer ramus markedly shorter than inner, 

 which is somewhat shorter than peduncle; both margins of both rami and peduncle armed with 

 numerous short spines; peduncle of second uropods relatively much less narrow than that of first, 

 somewhat shorter than inner ramus; outer margin armed with about five spines, inner with several 

 more; outer ramus much shorter than inner; both margins of both rami armed with numerous short 

 spines; terminal uropods extending beyond the others; rami flattened, lanceolate, subequal, much 

 longer than peduncle, with both margins of each furnished with numerous spines and plumose setae; 

 telson oblong, slightly tapering and rounded at tip. 



I ,ength, 16 nmi. 



Narragansett Bay (iudd); Vineyard Sound (Smith); Woods Hole; Gloucester; Grand Manan; 

 Halifax; Labrador; Greenland; Arctic regions; Norway; British Isles. 



I have examined numerous specimens and find transitional stages between forms which Sars 

 describes as Calliopius rathkei and those he refers to Ixniusculus. Smaller specimens usually present 

 the characteristics of rathkei. 



