596 



9. Potlocerus pusillus, l Gr. 0. Sars. 



(PI. 212, fig 1). 

 Podoceius minutus, G. O. Sars, Oversigt af Norges Crustaceer, I, p. 112, PI. 6, fig. 6. 



Body comparatively shorter and stouter than in the type species, 

 otherwise of a very similar appearance. Cephalon nearly as long as the first 

 2 segments of rnesosome combined, lateral lobes rather broad and angular in 

 front. Anterior pairs of coxal plates considerably deeper than the correspond- 

 ing segments; 1st pair in female obtusely quadrangular, in male considerably 

 produced in front; 2nd pair in male twice as broad as they are deep; 5th 

 pair with the anterior lobe nearly as deep as the preceding pair. Last pair 

 of epimeral plates of metasome scarcely produced at the lateral corners. 

 Eyes comparatively larger than in P. falcafus, and rounded in form, with 

 dark brown pigment. Superior antennae almost half the length of the body, 

 the last 2 peduncular joints subequal and each about twice as long as the 

 1st, flagellum half the length of the peduncle, and composed of only 5 arti- 

 culations, accessory appendage extremely minute. Inferior antennae somewhat 

 longer than the superior, and as usual more strongly built in the male, though 

 not nearly so robust as in P. falcatus, last joint of the peduncle about the 

 length of the penultimate and, like the latter, carrying fascicles of slender 

 bristles posteriorly, but without any clothing of ciliated hairs; flagellum slender, 

 4 articulate. Anterior gnathopoda nearly as in P. falcatus. Posterior gnatho- 

 poda in female less robust than in that species, propodos more regularly oval 

 in form, with the palm less strongly flexuous, and defined posteriorly by a 

 very slight angle armed with 3 small spines, in front of which there is a 

 small angular prominence; those in the young male having, as in P. falcatus, in 

 the middle of the palm of the propodos, a short digitiform projection. Pos- 

 terior gnathopoda in the adult male very powerfully developed, with the 

 propodos of a similar shape to that in P. falcatus, though very markedly differing 

 in the circumstance that the thumb-like process is considerably shorter and 

 broader, with the tip distinctly bilobed. Pereiopoda comparatively more slender 

 than in the type species and less densely setiferous. Last pair of uropoda with 

 the inner ramus less coarsely hooked. Telson small, and acutely produced at the 

 tip. Body variegated with irregular patches of a dark brown colour. Length of 

 adult female scarcely exceeding 5 mm, of male about the same. 



To avoid confusion with Ischyrocerus minutus Lilljeb., in case the latter genus should 

 not be accepted, I have thought it right to change the specific name of this form. 



