cl6 CARCINOLOGICAL STUüIEfcJ. 



of this Species closely resembles that of Gelas. arciiatus de 

 Haan, but it differs by the different form of the 

 front and by the existence of an accessory row 

 of small granules on the lower wall of the 

 orbits near the inferior margin. The front of 

 Gelas. arcuatus is more distinctly constricted at the insertion 

 of the eye-peduncles than in the other species; the frontal 

 furrow extends beyond the middle of the front , is narrow , 

 and its margins are parallel , but in Gelas. signatus the 

 frontal furrow does not or only scarcely reach the 

 middle of the front and it is broadly triangular, 

 with rounded tip, and with divergent lateral 

 margins (fig. ll"). The orbits are transverse, quite as 

 those of Gelas. arcuatus , but they are ornamented below 

 with an accessory row of fourteen or fifteen small granules 

 near the middle of the inferior margin , which are not 

 found in the species of de Haan. The lateral margins have 

 the same form and direction as those of Gelas. arcuatus , 

 as they have the same undulated course in the form of 

 a S. The abdomen of the male is a little less enlarged than 

 in the Japanese species. 



In both specimens the larger hand occurs on the left 

 side. The anterior and the lower margin of the arm are 

 finely granulate and the anterior margin presents a more 

 or less distinct, compressed and denticulate lobe at the 

 distal end. The outer surface of the wrist is smooth , the 

 upper one is finely granulate and the internal margin 

 somewhat denticulate. The hand (fig. lib) presents the same 

 elongate and slender form as that of Gelas. Dussumieri 

 and is a little more than once and a half as long as the 

 distance between the external orbital angles. The outer 

 surface of the palm is more finely granulate than in Gelas. 

 Dussumieri; like in this species the inner surface of the 

 palm is somewhat granulated in the middle and the two 

 ordinary oblique rows of larger granules are equally distinct 

 in both species. The fingers are twice and a half as long 

 as the palm , and therefore appear comparatively as long 



Notes from tlie Leyden jMuseum, "Vol. XIII. 



