rather strongly vaulted dorsally. Cephalic segment about twice as long as the 

 3 succeeding segments combined, and scarcely exhibiting the slightest trace 

 of a dorsal suture; rostral prominence well defined and pointed at the end. 

 Tail only slightly exceeding half the length of the anterior division; genital 

 segment rather large, occupying almost half the length of the tail, and con- 

 spicuously dilated in front of the middle; anal segment scarcely as long as the 

 preceding one. Caudal rami not much produced, though somewhat longer than 

 the anal segment, and only very slightly divergent; seta of outer edge attached 

 at a short distance from the end; apical setae not much produced, the inner 

 mediate one only slightly exceeding half the length of the tail. Anterior 

 antennae moderately slender and clothed with scattered comparativeiy short 

 setae; 2nd joint, as usual, the longest, though scarcely attaining the length of 

 the 2 succeeding joints combined; last joint fully as long as the penulti- 

 mate one. Posterior antennae unusually shotf and stout, and apparently 

 composed of only 3 joints, the outer 2 being wholly confluent; 1st and 

 2nd joints very massive and of about equal size, each having outside a 

 well-marked seta; distal part of the antenna (the combined 2 outer joints) 

 rather narrower than the proximal part, but of about the same length, and pro- 

 vided outside with a denticulated spine and 2 unequal setae, at the tip with 

 several curved setae, one of which is somewhat stronger than the others and 

 may represent the inner claw, the outer claw being exceedingly strong, knife- 

 shaped and irregularly denticulate along the outer sharpened edge. Maxillary 

 palp comparatively small but provided with 4 setae. Anterior maxillipeds with 

 the distal joint larger than usual; apical lash comparatively short and having 

 the margin coarsely dentate at the base. Posterior maxillipeds rather feeble, 

 but exhibiting a very conspicuous armature, 2 rather strong, almost claw-like 

 spines being attached to the inner edge of the propodal joint and a similar, 

 though smaller spine inside the dactylar joint. Natatory legs with the rami 

 comparatively slender and having the spines narrow dagger-like; terminal joint 

 of inner ramus in 1st pair obliquely oval in form, with the spine of the outer 

 edge attached close to the apex. Inner ramus of 4th pair rather small, not 

 nearly attaining the length of the first 2 joints of the outer combined, and 

 biarticulate, proximal joint without any seta inside, distal joint slightly attenu- 

 ated, with the apical spines very unequal in length. Last pair of legs with 

 the free joint very long and narrow, slightly curved and quite smooth outside. 

 Ovisacs oval in form and slightly divergent, extending scarcely beyond the tail. 

 Male, as usual, of smaller size than female, and moreover easily recog- 

 nisable by the greatly inflated genital segment. Posterior maxillipeds very 



