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taken together. Thorax distinctly narrower than the head, three 

 times as long as broad, nearly as broad behind as in front, with 

 perceptible, though faint, promesonotal and mesoepinotal sutures, 

 the former nearly straight, the latter arcuate. In profile the dor- 

 sal surface of the thorax is flattened, the epinotal declivity abrupt, 

 concave and marginate on the sides. Petiole and postpetiole each 

 about as long as broad, subrectangular , with rounded corners, 

 the postpetiole somewhat larger and broader than the petiole, 

 which in profile has an abrupt anterior, flattened dorsal and ab- 

 rupt posterior surface and a large, more or less rounded, com- 

 pressed antero-median ventral projection. The postpetiole is si- 

 milar in profile except that its posterior declivity is shorter and 

 its ventral projection thick and not compressed. Gaster elongate 

 elliptical, a little less than twice as long as broad; first segment 

 forming the greater portion of it, decidedly longer than the pet- 

 iole and postpetiole together, truncated at the base ; apical seg- 

 ments small and short. Legs rather stout. 



Subopaque; gaster slightly more shining. Body, except the 

 appendages, covered with foveol&e which are of the same size 

 and almost as dense on the gaster and pedicel as on the head 

 and thorax. 



Hairs pale yellow, reclinate, long and rather abundant on the 

 body, shorter on the legs and scapes. 



Ferruginous ; mandibles , clypeus and antennae , except the 

 giandiform terminal joint, darker and more brownish. 



Six specimens from Hilo. 



This species belongs to the subgenus Cysias as defined by 

 Emery , and closely resembles C. papuaniis Emery from New 

 Guinea and C. ausfralis Forel from Australia. From papuanus 

 the new species differs in sculpture, as the head is not more coarse- 

 ly foveolate than the remainder of the body , the head is di- 

 stinctly broader than the thorax, the latter has traces of promes- 

 onotal and mesoepinotal sutures and the an te ro -ventral projec- 

 tion of the petiole is larger ; from aiistralis it differs in being 

 much more opaque, with denser foveolae, and in having a some- 

 what longer head and decidedly more robust antennae. I have 

 followed Forel in placing C. silvestrli in the subgenus Syscia 

 and in not recognizing Cysias. This latter subgenus according to 

 the Swiss myrmecologist, is untenable, since C. biroi Forel is in- 

 termediate in the length of its first gastric segment between the 



