REPORT ON THE BRACHYURA. 
263 
produced antero-external angle of the merus of the outer maxillipedes, and in the dilata- 
tion of their exognath, certain species of the former genus nearly approach Ptychognathus. 
If the genera be thus defined, Gnathograpsm pilipes, A. Milne Edwards, will be better 
placed in Pseudograpsus than in Ptychognathus, where both Kingsley and myself have 
placed it. 
Platygrapsus, Stimpson. 
Platynotus, de Haan, Crust, in v. Siebold, Fauna Japonica, p. 34, pi. IX, 1835; name previously 
used. 
Platygrapsus, Stimpson, Proc. Acad. Nat. Sci. Philad., p. 104, 1858. 
This genus is very nearly allied in external appearance and in nearly all structural 
points to Pseudograpsus, but is distinguished by the form of the exterior maxillipedes, 
whose ischium-joint is short, very obliquely, not squarely truncated at the distal extremity. 
The merus-joint is large, distally truncated, and the next joint articulates with it near 
its antero-external angle, which is not produced as in Pseudograpsus ; the exognath also 
is narrower than in that genus. As in Pseudograpsus, the carapace is depressed, with 
the antero-lateral margins slightly arcuated and dentated ; the epigastric lobes are de- 
veloped; the post-abdomen of the male does not cover the whole width of the sternum 
at the base. The chelipedes are well developed, and the dactyli of the ambulatory legs 
are styliform and without marginal spines. 
The single species, Platygrapsus depressus, occurs on the shores and islands of 
China and Japan. 
Platygrapsus depressus (de Haan). 
Platynotus depressus, de Haan, Crust, in v. Siebold, Fauna Japonica, pp. 34, 63, pi. viii. fig. 2, 1835. 
„ ,, Milne Edwards, Ann. d. Sci. Nat., tom. cit., p. 199, 1853. 
Platygrapsus depressus, Stimpson, Proc. Acad. Nat. Sci. Philad., p. 104, 1858. 
„ „ Miers, Proc. Zool. Soc. Lond., p. 37, 1879. 
„ „ Kingsley, tom. cit., p. 211, 1880, et synonyma. 
Japan, Kobe, 50 fathoms, lat. 34° 38' 0" N., long. 135° V 0" E., Station 233a. (A 
small female bearing ova). 
5 . Lines. Millims. 
Length of carapace, . . . . . . . 3 6 '5 
Breadth of carapace, ....... 3^ 7 
