GRAPSIDAE. 



This large family contains some widely spread genera and above all the true Grapsi, 

 that are most conspicuous on all sandy and rocky beaches in the tropics. The carapace is 

 squarish, the front broad and much exceeding the length of the short and thick eye-stalks, 

 the external maxillipeds are widely gaping, the chelae are very often provided with a tuft of 

 hairs on the palm or in the cleft of the fingers. 



Like the Ocypodidae all species are essentially littoral, keeping quite close to the shore, 

 in shallow water, or haunting the beach, where they are found running about with marvellous 

 speed and throwing themselves headlong into the water when pursued. As a rule they do not 

 burrow but shelter themselves under stones. Some species keep to estuaries, to the mouth of 

 rivers or even to entirely fresh water; one genus [Geograpstis) may be called almost terrestrial; 

 on the other hand such genera as Planes and Varima (especially the former) are wont to 

 cling to floating objects and may be carried along all throughout tropical and subtropical 

 seas : as is well known Planes is even a common inhabitant of the Sarcjassum weed. 



The family is subdivided into four subfamilies: Grapsinae, Sesarminae, J'aruninae and 

 Plagusiinae^ for the discrimination of which a reference to Alcock's ^) or Borradaile's -) paper 

 is sufficient. 



Subfam. Grapsixae. 



The four Indo-Pacific genera are well discriminated by Alcock's most useful memoir and 

 there is to need to repeat his key to Grapsus, Gcograpsus, Metopograpstis and Pachygrapsus •'). 



GrapsuS Lamarck. 

 1801. GrapsHS Lamarck. Syst. An. sans vert., p. 150. 

 Subsequent writers frequently have included into Grapsus several species which really 

 are to be referred to other genera. The true Grapsi are separable into only a few species, 

 ,two of which are again subdivided into subspecies. 



i) Journ. As. Soc. Bengal, v. 69, prt. 2, 1900, p. 389 — 390. 



2) Ana. Mag. Nat. Hist. (7) v. 19, 1907, p. 485. Kingsley (Proc. Acad. Xat. Sc. Philadelphia, 18S0, p. 1S7) has given 

 most useful key to the genera then known: his analytical tables of the genera are unfortunately often unreliable. 



3) Leplosrapstis H. Milne-Edwards with apparently one species only, L. variegatus (Fabricius) (Kingsley, I.e. p. 196, Orimann 

 Zool. Jahrb., Syst., Bd 7, 1894 p. 707) is not included; for the species, though occasionally recorded from Australia, Tasmania and China 

 is chiefly a West American one. 



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