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Carapace widened proximally (lateral margins distinctly 

 convergent backward). Inner orbital lobe coalesced with 

 the front over nearly the whole inner margin, sharp 

 and keeled M. inessor Forsk^l 



4. Front broader, orbits small M. eydouxi H. Milne-Edwards ^) 



Front narrower, orbits wide - . M. tJmkuhar (Owen) 



5. Lateral margins of carapace much convergent backward; 



distance between external orbital angles to length of 

 carapace as 100 : 84 — 87°/^ in small and medium-sized 



and 100:89 — 92°/^ in large specimens M. latifrons (White) 



Lateral margins of carapace less convergent backward; 

 distance between external orbital angfles to length of 

 carapace as 100 : + 80°/^ M. inacitlaUisW. Milne-Edwards 



6. Postfrontal lobes little prominent; front not strongly de- 



clivous; internal orbital lobe broad and rounded at tip, 

 coalesced with the front along a short distance (as in M. 

 tJnikuhar). Dactyli of walking legs only slightly shorter 



than propodites , . . . . M. qtiadridentatiis Stimpson ") 



Postfrontal lobes more distinct and sharply separated; front 

 strongly deflexed ; internal orbital lobe narrow and acute 

 at tip, coalesced with the front along greater distance 

 (as in M. messor). Dactyli of walking legs much shorter 

 than propodites J/. c;^<?«;«Vz/.? (Jacquinot et Lucas) 



I. Meiopo^rapstis inessor (Forskal). 



Literature: Alcock, I.e. p. 397. Description: DE Man, Journ. Linn. Soc. London, v. 22, 

 1 888, p. 144, pi. 9, f. II; Arch. Naturg., Jahrg. 53, i., p. 361, pi. 15, f. 6. 



Grapsiis (Pachygrapsus) aethiopkus ^) Hilgendorf. v. d. Decken's Reis. Ost-Afrika, Bd 3, i,. 

 Crust., 1869, p. 88, pi. 4, f. 2. 



Stat. 47. Bay of Bima, Sumbavva. 12 c? (mostly juv.), i 9 with eggs. 

 Stat. 71. Macassar, i cf- 



MiERS *) described a subsp. frontalis from Macassar and other localities, which seems to 

 be an individual variation and has not been maintained by subsequent authors, 



Another subspecies [gracilipes) has been founded by de Man ^), originally from the 



1) Ann. Sc. Nat. (3) t. 20, 1853, p. 165. It must be admitted, Ihat ihe differences between this species and M. thitkuhar are 

 insignificant, and Kingsley already identified both species with M. messor \ the same has been done in recent years by Miss Rathbun 

 (Bull. U.S. Fish Coram, for 1903, v. 23, prt 3, 1906, p. 839) in dealing with the marine Brachyura and Macrura of the Hawaiian Islands. 

 It is from this very locality that both M. eydouxi and M. thiikti/iar originate. 



2) Description: de Man, Zool. Jahrh., Syst., Bd 9, 1895, p. 76, Bd 10, 1898, pi. 28, f. 16. 



3) Even in recent days the species has been referred to under this name by Doflein (Wiss. Erg. Tiefsee-E.\p. "\'aldivia", Bd 6 

 (Crust.), 1904, p. 130, and implicitly ranged with Pachygrapsus. With the name Metopograpsus viessor the author is apparently unacquainted. 



4) Ann. Mag. Nat. Hist. (5) v. 5, p. 311; Rep. "Challenger", Brachyura, 1886, p. 258. 



5) Notes Leiden Mus., v. 13, 1891, p. 49, pi. 4, f. 14. 



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