CRUSTACEA NORTH PACIFIC EXPLORING EXPEDITION 25 



kong ; also on fuci at low-water mark in the harbor of Simoda, 

 Japan. 



Genus MEX.^THIUS ^lilne Edwards 



27. MENiETHIUS SUBSERRATUS ' Adams and White 



Mcncethius subserratus Adams and White, Voy. Samarang, p. 18, pi. iv, 

 figs. I, 2. Dana, U. S. Expl. Exped., Crust., i, 122, pi. iv, fig. 7. 



This species would seem scarcely to differ from M. monoceros, 

 judging from Riippell's figure, which is a fair representation of 

 some of our Chinese specimens. But the members of this genus are 

 greatly variable and a great number of specimens is required for 

 their accurate determination. 



It was taken by the expedition at Hongkong, China, and at the 

 Amakirrima Islands. 



It is also reported from the Philippine, Fiji, and Samoan Islands. 



28. MEN^THIUS DENTATUS == Stimpson 



Plate III, Fig. 6 



Menccthius dentatus Stimpson, Proc. Acad. Nat. Sci. Phila., ix, p. 219 

 [26]. 1857. 



This species has much resemblance to M. subserratus, but the Idt- 

 ■eral teeth and the tubercles of the dorsal surface are much more 

 prominent than in any specimens of that species which have come 

 under our notice. The following description is taken from an adult 

 male: Proportion of breadth of carapax to length, i : 1.5. Depres- 

 sions between the regions deep. The cardiac region is very prom- 

 inent and ample, occupying one-third the width of the carapax. 

 Lateral teeth sharp and subtriangular ; the two teeth on the antero- 

 lateral margin prominent, projecting well over the sides of the cara- 

 pax, and bilobate, wnth the anterior lobe smallest. The two tubercles 

 on the gastric region are sharply protuberant and covered in front 

 with crispate setae. The surface is elsewhere clean, with the excep- 

 tion of a slight pubescence on the sides and a dense pilosity on the 

 rostrum. Interorbital space rather harrow, very smooth and flat, 

 with the exception of the bituberculate anterior extremity of the gas- 

 tric region. Rostrum rather long, curving a little upward toward the 

 extremity. Praeorbital teeth very long, pointing forward in a longi- 

 tudinal direction. Chelopoda large ; the hand rather compressed ; 



^ Mencethius monoceros (Latreille). 

 ' Mcncrthius monoceros (Latreille). 



