RATHBUN: CRABS FROM THE MALDIVE ISLANDS. 125 
The chelipeds are massive, unequal; the larger one is about twice as long as 
the carapace. The upper margin of the merus has a few denticles and a blunt 
subterminal tooth ; the posterior margin and inferior surface are crossed by a 
subterminal groove. The inner angle of the carpus forms a blunt, almost 
rectangular tooth. The palm is nearly as wide as the length of its upper mar- 
gin ; the dactylus is shorter than that margin in the larger cheliped, and longer 
in the smaller one. The lower margin of the propodus has a shallow sinus 
between palm and finger. ‘The fingers are broad, white, not gaping, occludent 
Inargins irregularly dentate, tips crossing, outer and inner surface each with 
two lines of larger puncte. 
The surface of the chelipeds is similar to that of the carapace except that the 
fine wrinkles are interrupted by minute transverse irregular smooth patches. 
The merus joints of the ambulatory legs are devoid of a spine on the upper 
margin. The propodus and dactylus of the last pair are considerably shorter 
and broader than in the three preceding ; the propodus is wider than half of its 
length measured on the anterior margin ; the dactylus is straight, not curved, 
on its anterior margin. 
The first segment of the abdomen of the male is hidden under the carapace ; 
the second is narrowed at the sides and does not fully cover the sternum ; the 
third reaches the coxe of the fifth pair of legs ; the remaining segments are 
very narrow, the terminal one much longer than broad. 
Dimensions. — Length of carapace, 5.1 mm.; width at exorbital angles, 
7.5 mm. ; greatest width, 7.8 mm. ; posterior width, 5.5 mm.; width of front 
between the antennal notches, 2.6 mm. ; width of front between the supra- 
orbital margins, 3.4 mm. 
Type locality. — Gan Island, Addu Atoll, at anchorage, 20 fathoms, January 
6; one male. 
This species differs from G. rhomboides (Linnezus) of Europe, in its wider 
front and shorter eyes, in the carapace being widest at the line of the lateral 
teeth, in the absence of a spine from the legs, in the much narrower abdomen 
of the male. 
GRAPSIDA. 
Metasesarma rousseauxi Mitne Epwarps. 
Metasesarma rousseauxit ALcock, Journ. Asiatic Soc. Bengal, LXIX. 427, 1900, 
and synonymy. 
Metasesarma rousseauzi BORRADAILE, Fauna Maldive Arch., I. part I. pp. 68 and 
97, 1901. 
Marco, Fadiffolu Atoll, at anchorage ; one male, one female with ova. In 
the male, 9.2 mm. long by 10.2 mm. wide, the fingers when apposed, gape 
except at the tips. 
