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depths, a very remarkable distribution, being found (i) off the West Indies 

 and Atlantic coasts of the United States as far as 41° N., (2) in the Eastern 

 Atlantic from the Azores and coast of Portugal to Cape Verde, and (3) in the 

 Arabian Sea, Bay of Bengal, and Andaman Sea. Outside these areas only 

 one species is at present known, and that from off the coast of New South 

 Wales, 



The Indian species are two in number, and both of them are merely 

 varieties of Atlantic forms. 



Key to the Indian species of the genus Sympagurus. 



1. The upper border of the right palm is ornamented with two 



longitudinal sharply-serrated crests ^ _. ... S, btcristatus. 



II, The upper border of the right hand has a single serrated crest, 



inside which is a second non-cristiform row of serrations ^ S. arcnntus. 



1. Sympagurus arcuatus, Edw. and Bouvier. 



Sympagunis arcuatus, Milne Edwards and Bouvier, Mem. Mus. Comp. Zool., Harvard, XIV., 

 No. 3. 1893, p. 67, pi. v., f5g. 21-28; and Bull. Soc. Zool. France, XXII. 1897, p. 133 (see also 

 Crust. Decap. Hirondelle et Princesse Alice, Monaco, 1899, p. 56). 



Distribution: West Indies, 138 to 229 fathoms. 



Sympagurus arcuatus, E. & B. var. monstrosus, Alccck. Plate X., fig. 5. 



? Parapasurus monstrosns, Alcock, Ann. Mag. Nat. Hist., .March, 1894, p. 243. 



Sympagurus monstrosns, Henderson, J. A. S. B., LXV., 1896, pt. 2, p. 533 : Alcock, Cat. Ind. 

 Deep Sea Crust., 1901, p. 223 Illustrations Zool. Investigator, Crust., pi, xxxii , fig. 4. 



Differs from the description and figures of the West Indian form only in having the right 

 hand more setose, and this to a variable extent. 



Carapace strongly calcified only in the hepatic regions ; rostrum though 

 faintly carinated almost obsolete. 



Eyestalks stout, dorsally setose, not much more than half the length of 

 the anterior border of the carapace, reaching nearly to the end of the 2nd 

 joint of the antennular peduncle and nearly to the end of the antennal 

 peduncle. Eyes large, reniform : ophthalmic scales sharply acuminate. 



Antennular peduncle more than two-thirds the length of the carapace, 

 more than half its length being contributed by the terminal joint. The 

 antennal acicle, which reaches to, or almost to, the end of the antennal 

 peduncle, is sinuous and has its inner border serrated. Antennal flagellum 

 nearly twice as long as the body. 



The right cheliped, which is very massive, is from 2\ to 2^ times the 

 length of the carapace and is setose, but not so thickly so as to in any way 

 obscure the surface sculpture : the massive and sharply-trigonal carpus is 

 longer than the combined ischium and merus and as long as, or longer than 



