G. 0. SARS. [SEC. ARC. EXP. FBAM 



of the 3 succeeding segments rounded and sub-contiguous; penultimate 

 segment deeply emarginated behind. Last pedigerous segment very 

 small. Urosome much narrower than the anterior division and scarcely 

 attaining half its length, genital segment, as usual, much the largest; 

 last segment very short. Caudal rami likewise short, broader than they 

 are long, and transversely truncated at the end; apical setae unusually 

 short and less unequal than in the other species, the inner medial seta 

 but little longer than the outer, and scarcely exceeding the urosome in 

 length, being remarkably dilated for the greater part of its length; inner- 

 most seta longer than the outermost, both very thin. Anterior antennae 

 comparatively short, with the 2nd joint much the largest, the 2 suc- 

 ceeding joints gradually smaller, terminal part about twice the length of 

 the preceding joint. Posterior antennae rather small, but otherwise of 

 normal structure. Mandibular palp with the inner ramus shorter and 

 stouter than the outer. Anterior maxillipeds with the terminal claw 

 very strong and abruptly bent at the tip, appendicular lobe extremely 

 small with only a single minute bristle at the tip. Posterior maxillipeds 

 comparatively more powerful than in the other species. 1st pair of 

 legs exhibiting the structure characteristic of the genus, outer ramus 

 exceeding half the length of the inner, and having the penicillate spines 

 comparatively thin, inner ramus with the 1st joint rather dilated, 2nd 

 joint not much narrowed and scarcely longer than the 1st, last joint 

 very small, with 2 unequal claws at the tip, the inner one much the 

 larger and distinctly penicillate. Natatory legs very fully developed, 

 with the rami, especially those of the anterior pairs, rather broad and 

 subequal in length; those of 4th pair, however, rather more slender. Last 

 pair of legs not much produced, distal joint lamellar, oblong oval in 

 form, and provided at the end with 4 comparatively short setae, inner 

 expansion of proximal joint short, triangular, and tipped with 2 unequal 

 setae. Ovisac oblong in form, and extending considerably beyond the 

 tip of the caudal rami. 



Male, as usual, much smaller and more slender than female, and 

 having the anterior antennas slightly transformed, subprehensile. Last 

 pair of legs very small, with the inner expansion of the proximal joint 

 quite obsolete. Genital lobes each with a strong spine and two small 

 hair-like bristles. 



Length of adult female about 1 mm. 



Remarks. - This is a very distinct and easily recognisable species, 

 being especially distinguished by the greatly inflated anterior division of 

 the body and the unusually short caudal setae. 



