RATHBUN: CRABS FROM THE MALDIVE ISLANDS. 131 



Two types ( $ and 9 ) of Dana's Xiphonectes longispinosus are preserved in 

 the Museum of Comparative Zoology. The surface of the carapace is very 

 uneven, the frontal teeth rounded, the intervening sinuses shallow and of equal 

 depth, a well-marked sinus below the outer orbital angle, the inner suborbital 

 angle rounded, the nierus of the maxilliped reaches part way along the inner 

 suborbital tooth. Width of male between tips of lateral spines, 14.2 mm., of 

 female, 12.8 mm. 



Thalamita oculea Alcock. 



Thalamita oculea Alcock, Journ. Asiatic Soc. Bengal, LXVIII. 76 and 91, 1899. 

 IIlus. Zool. Investigator, Crust., pt. VIII. pi. XL VIII. figs. 3. 3a, 1900. 



Qan Island, Addu Atoll, 20 fathoms, at anchorage, January 6 ; one imma- 

 ture male. 



Nallandu Island, 24 fathoms, at anchorage, January 18; one young. 



In the male (5.9 mm. long), the fourth lateral tooth is much smaller than 

 the fifth. That spine on the outer margin of the upper surface of the hand 

 which is remote from the finger, though smaller than the other spines, is well 

 marked. The length and breadth of the sixth abdominal somite are subequal. 



In the young specimen the fourth lateral tooth is rudimentary, the fifth is 

 subequal to the third. 



? Archias.i sp. 



Nallandu Island, 24 fathoms, January 18. Two very young specimens, one 

 2.6 mm. long and 3.2 mm. wide, are not referable to any known species. The 

 carapace is quadrate or Thalamita-like, while the narrow, elongated basal joint 

 of the antenna and the remoteness of the inner suborbital angle from the front, 

 place the species in the neighborhood of Archias, Lupocyclus, and Carupa. 



The carapace is somewhat granulous and traversed by two transverse ridges, 

 one across the gastric region, the other further back, connecting the posterior 

 of the lateral teeth. The intra-orbital width is a little over half the width of 

 the carapace ; the margin of the front is divided into four shallow lobes, the 

 inner pair about one-third as wide as the outer, and slightly more advanced. 

 Inner supra-orbital angles obscurely defined. 



The antero-lateral margins are straight and parallel to each other, cut into 4 

 subequal, sharp-pointed teeth with a rudiment of another between the last two. 

 The postero-lateral margins are concave and moderately convergent. 



The orbits are very large (as also the eyes), with slight dorsal inclination; 

 no fissures visible on the margin. The inner end of the lower margin is angular 

 but not prominent, projecting very little beyond the buccal cavity. 



The basal joint of the antenna is more than twice as long as broad, it widens 



1 Archias Paulson, Crustacea of the Red Sea, 1875, p. 56. 



