io 7 



Front short, anterior margin with only two minute notches, 

 near external angles, median lobe broad and straight; 

 surface of carapace little uneven ; a granulate ridge runs 

 inward from the third lateral tooth ; external maxillipeds 

 strongly gaping, ischium and merus narrow and long, 

 the latter auriculate E. leptognathus Rathbun l ) 



2. Lateral margins of carapace nearly straight; anterior margin 



of front indistinctly four-lobed, median sinus ver)- shallow E. rcctus Stimpson ~) 

 Antero-lateral margins of carapace diverging backward; 

 anterior margin of front distinctly four-lobed .... 3 



3. Carapace flattened; anterior margin of front divided into 



four lobules, the external ones of which are sharply 

 angular; posterior (4" 1 ) antero-lateral tooth of carapace 



very minute. Chelae (of cf) wrapped in a thick hairy muff E. japonicus de Haan 8 ) 

 Carapace vaulted, with four sharply-edged epigastric lobes; 

 anterior margin of front with four acute teeth ; posterior 

 (4" 1 ) antero-lateral tooth of carapace not much smaller 

 than the preceding one. Chelae (of (?) much less clothed 

 with hairs E. sinensis H. Milne-Edwards 4 ) 



Subfam. Sesarminae. 



This subfamily is characterized by the front being nearly always strongly deflexed, so 

 that the postfrontal lobes are sharply-ridged anteriorly, and by the external maxiljipeds being 

 provided by an obliquely-longitudinal hairy ridge on the ischium and especially on the merus, 

 which latter is generally not auriculate and mostly of an oval shape. In the typical represen- 

 tatives of this subfamily {Sesarma, Metasesarma, Sarmatium) the pterygostomian regions and 

 side-walls of the carapace are covered with a fine reticulation of hairy lines and the terminal 

 segment of the abdomen of the 9 ' s strongly pushed into the preceding segment. 



Key to the Indo-Pacific genera : 

 1 . Pterygostomian regions and side walls of carapace covered 



with a fine reticulation of intercrossing hairy lines . . 2 



1) Proc. U.S. Nat. Mus., v. 46, 1913, p. 353, pi. 33, f. 2 — 3. Hab. Shanghai. 



2) Eriochirus rcctus Stimpson, Proc. Ac. Nat. Sc. Philadelphia, 1858, p. 103; Eriocheir r. Kingsley, Proc. Ac. Nat. Sc. Phila- 

 delphia, 1880, p. 210; Eriochirus r. Stimpson, Smithson. Inst., Miscell. Coll., v. 49, 1907, p. 125. Hab. Macao (China). 



3) Faun. Japon., Crust., 1835, p. 59, pi. 17; Eriochirus j. H. Milne-Edwards, Ann. Sc. Nat. (3) t. 20, 1853, p. 176; Eriocheir j. 

 Kingsley, Proc. Ac. Nat. Sc. Philadelphia, 1880, p. 210; Ortmann, Zool. Jahrb., Syst., Bd 7, 1894, p. 716; Eriocheir j. Rathbun, Proc. 

 U.S. Nat. Mus., v. 26, 1903, p. 24; Eriochirus j. Stimpson, Smithson. Inst., Miscell. Coll., v. 49, 1907, p. 124. Hab. Japan. 



4) Eriochirus sinensis H. Milne-Edwards, Ann. Sc Nat. (3) t. 20, 1853, p. 177; Arch. Mus. Paris, t. 7, 1853, p. 146, pi. 9, f. 1 ; 

 Heller, Reise "Novara'', Crust., 1865, p. 52; Eriocheir s. Kingsley, Proc. Ac. Nat. Sc. Philadelphia, 1880, p. 210; Eriochirus s. Koelbel, 

 Wiss. Erg. Reise Széchenyi 1877 — 1SS0, Bd 2, 1898, p. 572. Hab. Shanghai. 



107 



