MARINE CRUSTACEANS. 



III. THE XANTHIDAE AND SOME OTHER CRABS. 



By L. A. BoRRADAiLE, M.A., Lecturer in Natural Sciences at Sehvy 



College, Cambridge. 



")i 



(With Text-figures 41—60.) 



The in-stalment of the Marine Crustaceans of the Expedition described in this paper 

 includes, besides the Xanthidae, two new genera, possibly allied to them, and a couple of 

 small families — the Atelecyclidae and the Hapalocarcinidae — which are taken here for reasons 

 of convenience. Some remarks on the natural history of the crabs will be found under the 

 headings of the families, genera, etc. to which they belong. 



Fig. 41. Types of the Xanthid Crabs. A. Actaea fossulata, resembling water-worn coral pebbles and found in the 

 lower parts of a coral stock or other situations into which pebbles could be washed. B. CarpiUus exsculptus, 

 adapted for passively withstanding surf and currents. C. Euxanthus exsculptus var. rugosus, found amongst stones, 

 etc. on the reef. B. Chlorodius harhatus. E. Domoecia hispida, a coral crab. F. Trapezia ferruginea, also a coral 

 crab. The drawings are not made to scale, i? is a large crab, C and F of moderate size, and the others small. 



Family Xanthidae. 



Of all the families of crabs the Xanthidae are the most numerous in genera and species, 

 and the most varied in form, though this preeminence is seen chiefly in the Tropics, and 

 there best in the littoral belt, where they are to be found in every possible position. 



