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1903- Pachygrapsus planifrons Borradaile. Faun. Geogr. Maldives etc, v. 1, p. 432. 



1905. Pachygrapsus planifrons Lenz. Abhandl. Senckenb. Gesellsch., Bd 27, p. 370. 



1906. ? Pachygrapsus longipes Rathbun. Buil. U.S. Fish Comm. for 1903, v. 23, prt 3, p. 840, 



pi. 8, f. 7. 



1907. ? Pachygrapsus longipes Rathbun. Mem. Mus. comp. Zool. Harvard Coll., v. 35, n° 2, p. 30. 

 191 1. ? Pachygrapsus longipes Rathbun. Transact. Linn. Soc. London (2) v. 14, p. 242. 



Stat. 34. Labuan Pandan, Lombok. 1 Q. 



De Man l ) observed, that P. loiigipes is most nearly related to, if not identical with, his 

 /'. planifrons, and indeed, both descriptions and figures agree very well. My specimen, anyhow, 

 is certainly P. planifrons, though in some points there is some disagreement. Firstly the front is 

 not nearly horizontal, but obliquely derlexed, and secondly the merus of the external maxilliped 

 is not nearly circular, as depicted by de Man, but agrees with that of P. propinquus; the 

 inner margin of the ischium is concave, as in P. laevis. The infra-orbital border is entire, not 

 dentate, as in P. plicatus, and strongly sloping backward in its outer half. The propodites of 

 the penultimate pair of legs (which are the most elongate) are fïve times as long as broad, 

 which agrees with P. longipes; the propodites of all the legs are not unarmed, as de Man 

 says, but there are two movable spines at the distal end of the inner or posterior margin, 

 besides the usual stiff hairs of these joints. 



Metopograpsus H. Milne-Edwards. 

 1853. Metopograpsus H. Milne-Edwards. Ann. Sc. Nat. (3) t. 20, p. 164. 



The genus has been sorrietimes confounded with Pachygrapsus^ but the antennae are 

 always excluded from the orbit by means of the broad inner orbital lobe, that joins the front. 

 In the literature, nevertheless, some cases are mentioned where there is a more or less wide 

 gap between the orbital lobe and the front. 



De Man 3 ) was the first to discriminate exactly the species, but up to recent times some 

 authors continue to regard some species as identical with, or at most varieties of, others. Yet 

 Kingsley 3 ) undoubtedly goes too far in admitting only three species. 



Key to the species : 



1. Antero-lateral margins of carapace without tooth behind 



external orbital angle 2 



Antero-lateral margins of carapace with one tooth behind 



external orbital ansfle . . ■ 6 



2. Walking legs short, dactyli nearly as long as propodites . 3 

 Walking legs longer, dactyli distinctly shorter than propodites 5 



3. Carapace less widened proximally (lateral margins scarcely 



convergent backward). Inner orbital lobe coalesced with 

 the front over a short distance, rounded, not keeled . 4 



1) Ree. Ind. Mus. Calcutta, v. 2, pit 3, 1908, p. 21S. 



2) Arch. Naturgesch., Jahrg. 53. I., 188S, p. 359 — 360. 



3) Proc. Ac. Nat. Sc. Philadelphia, 1SS0, p. 190 — 191. 



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