CRUSTACEA NORTH PACIFIC EXPLORING EXPEDITION 99 



filled by the palpi of the outer maxillipeds. There is no piliferous 

 crest on the outer maxillipeds, which are rather broad and gaping, so 

 as to leave a rhomboidal space between; the meros-joint is but little 

 longer than broad. Chelipeds robust, smooth externally, hairy 

 within ; hand very thick, and about three-fourths as broad as long, 

 with glossy outer surface ; fingers short, acute ; dactylus armed with 

 a strong tooth at the middle of the inner edge ; immovable finger 

 minutely crenulated on the inner edge. Ambulatory feet compressed, 

 slightly canaliculated above, nearly smooth; meros-joint very hairy, 

 the other joints almost naked. Abdomen sufficiently broad, oblong, 

 not mAich tapering, seven-jointed; third joint swollen on each side of 

 the median line. Dimensions of carapax : Length, 0.26 ; breadth, 

 0.341 inch. 



The above description includes some generic characters, but is 

 • given in full for the better illustration of the genus. 



A single specimen was taken at Loo Choo. 



156. METAPLAX LONGIPES Stimpson 



Metaplax longipcs Stimpsox, Proc. Acad. Nat. Sci. Phila., x. p. 97 [43], 

 1858. 



One specimen only, a male, of this species was collected, of which 

 the following is a description. Carapax small in proportion to the 

 length and size of the limbs. Proportion of length to breadth, 

 I : 1.33. The greatest breadth is across the middle. Surface some- 

 what uneven, but glossy and punctate about the middle and anterior 

 portions. There are two conspicuous areolets on each side, marked 

 off by transverse depressions arising from the lateral fissures. On 

 the postero-lateral slope the surface is pubescent and marked with 

 two strise or raised lines proceeding from marginal fissures ; the an- 

 terior stria transverse, the posterior one oblique. Front very broad. 

 Frontal region deeply and broadly excavated longitudinally along the 

 middle. Lateral margin three-notched, the first or anterior notch 

 very deep, separating a strong tooth, which is somewhat turned, up; 

 the other notches very slight. Eyes stout, of moderate length. Infra- 

 orbital margin seven-lobed, lobes rounded, smooth, glossy, decreasing 

 in size outwardly, the innermost lobe being the largest and most pro- 

 jecting, somewhat curving downward. Epistome ample, convex. 

 Antero-inferior regions granulated and sulcated near the mouth, 

 pubescent near the lateral margins. Beneath the infraorbital margin 

 the sulcus is very deep, and under the internal lobe of this margin 

 there is a deep cavity. External maxillipeds rhomboidally gaping, 

 profoundly sulcated, making the inner oblique piliferous crest very 



