1909.] CRUSTACEA FROM CHRISTMAS ISLAND. 707 



and broad, not reaching front ; the short flagellum standing in 

 orbital hiatus. 



Endostomial ridges veiy slightly developed, not reaching to 

 anterior margin of buccal frame. 



Ohelipeds massive, unequal in both sexes ; fingers not hollowed 

 at tip. 



Abdomen of male with third to fifth somites coalesced. 



Type species, L. alcocki, sp. n. 



The little crab described below presents a combination of 

 characters which seems to exclude it from any of the existing 

 genera of Xanthidse. The great width of the carapace gives it 

 the facies of a Liomera, but it differs widely from that genus and 

 its immediate allies in the proportionate width of the fronto- 

 orbital boi'der, a character Avhich would refer the species to the 

 neighbourhood of Xanthodes in the sub-family Chlorodina^ of 

 Alcock's classification. The massive chelipeds recall those of the 

 Trapezioida, but in this character Liomera longimcma A. M.-E. 

 (Crust. Miss. Sci. Mexique, p. 240, pi. xlvi. fig. 1) makes some 

 approach to the new sj)ecies. 



Lt.-Col. Alcock, F.R.S., to whom I have fortunately been able 

 to submit the specimens of this crab, tells me that he considers 

 Liomera sodalis Ale. (Jour. Asiatic Soc. Bengal, Ixvii. (2) p. 88, 

 1898) to be probably congeneric with it. 



LlOXANTHODES ALCOCKI, sp. n. (Plate LXXII, figs. 1-3.) 



Carapace a little less than twice as broad as long, strongly convex 

 antero-posteriorly, slightly so from side to side ; surface smooth 

 and polished, without inter-regional markings except for a shallow 

 meso-gastric groove and a pair of crescentic depressions parallel to 

 the inner edges of the orbits. The greatest width is well in front 

 of the middle of the carapace and the straight postero-lateral mar- 

 gins are strongly convergent. The strongly arched antero-lateral 

 margins show the faintest possible traces of three teeth or lobes, 

 and in front of the second and third of these on the dorsal surface 

 is a shallow pit in which are set a few hairs. The front is very 

 mvich deflexed and its margin is one-third of the width of the 

 carapace or a little less ; there is a shallow median notch, and the 

 lateral lobes are nearly straight and not separated from the inner 

 supra-orbital angles. The orbits are very large, and the eyes, 

 when retracted, are incompletely hidden ; the fronto-oi-bital width 

 is about two- thirds of the width of the carapace. 



The basal antennal segment is short and broad, reaching to the 

 inner sub-orbital angle but not to the front. It appears to touch 

 a small downward process from the front. 



The endostome has a pair of very slight ridges which do not 

 nearly reach its front margin. 



The exopod of the third maxiilipeds is about half as wide as the 

 ischium ; the merus is broader than long ; the ischium has a longi- 

 tudinal groove. 



The chelipeds are very massive and very unequal in both sexes ; 



48* 



