GRAPSOIDEA. 319 



long, being shorter than the breadth of the carapax. The hand at 

 base is only fine granulous ; the upper and moveable finger is broadest 

 towards base and narrow towards apex ; the lower finger has the apex 

 curved outward ; the arm is not crested on the anterior margin. It 

 may be an individual of the G. maracoani, with the right or large 

 hand partly grown after mutilation. Length of carapax, twelve and 

 three-fourths lines ; breadth, eighteen and three-fourths lines ; breadth 

 across the anterior angles slightly greater than that a short distance 

 posteriorly. 



G. maracoani, Latr. Encyc, pi. 296, f. 1; Edwards, ii. 51. 



Genus HELCECIUS, Dana. 



Gelasimo affinis, antennis intemis longitudinalibm, juxta frontem iitrin- 

 que insitis, externis fronte paidum remotis, articido maxUlipedis ex- 

 terni 2>th breviore quam 2dm. Pedes maris antici siibceqid. Articuli 

 rnaxUlipedis externi 2dus otlusque sidco lineato fere longitudinalibene 

 notati. Abdominis articidus 2d us maris sterno vix aiigustior. 



Belated to Gelasimus, the inner antennae being longitudinal either 

 side of the front, and the outer at a distance from the front, and 

 the third joint of the outer maxillipeds being much smaller than the 

 second. Anterior feet of mcde subequal. Second and third joints 

 of outer maxillipeds marked with a linear sulcus, which is nearly 

 longitudinal. Second joint of male abdomen hardly narrower than 

 the sternum behind. 



One of the species here included, the cordiformis, has been referred 

 to Gelasimus. But in Gelasimus, the outer maxillipeds have seldom 

 the sulcus here described, ^he anterior feet are always very unequal, 

 and the male abdomen at base is much narrower than the sternum 

 behind. Besides, the habit is different. The buccal mass is some- 

 what projecting, approaching that of Doto and Myctiris; the surface 

 just back of the anterior angles of the carapax is more abruptly inclined, 

 being nearly vertical for a short distance, which gives this portion of 

 the animal a fulness not seen in Gelasimus, and the orbits the appear- 

 ance of a somewhat lower position, in a front view. Yet the general 



