74 HYMENOPTERA. 



metathorax truncate, the truncation smooth and shining, the 

 lateral angles of its verge recurved ; the coxae and femora ferru- 

 ginous, the apex of the latter black. Abdomen : the scale sub- 

 quadrate, and armed with four acute angular spines on its supe- 

 rior margin. 



Hob. Australia (Melbourne). 



55. POLYRHACHIS HEXACANTHUS. 



Formica hexacantha, Erichs. Wiegm. Archiv (1842), 260. 231 $ . 

 Hab. Tasmania. 



Species of Brazil. (Sp. 56-58.) 



56. POLYRHACHIS BISPINOSUS. PI. XIII. fig. 1. B.M. 



Formica bispinosa, Oliv. Encycl. Meth. vi. 502. 60. 



Latr. Hist. Nat. Fourm. 133. pi. 4. f. 20 . 

 Formica fungosa, Fabr. Ent. Syst. Supp. 281. 42; Syst. Piez. 

 410. 60. 



Hab. Cayenne; Brazil (Santarem). 



57. POLYRHACHIS SPINICOLLIS. 



Formica spinicolle, Latr. Voy. Humb. et Eonpl. Zool. ii. 99. 



pi. 38. f. 6, 7 & 8-10. 

 Hab. Brazil (Rio Negro). 



58. POLYRHACHLS RUGOSUS. B.M. 



Worker. Length 5-- lines. Black : the abdomen densely 

 clothed with pale golden silky pubescence. Head elongate and 

 coarsely rugose ; eyes very prominent, placed backwards on the 

 sides of the head ; the head much narrowed behind the eyes, 

 before the eyes it is slightly widened to the angles of the anterior 

 margin, which is rounded ; the mandibles large and triangular, 

 finely denticulate on their inner margin ; antennae elongate and 

 slender, the scape with a number of erect, long hairs. Thorax 

 elongate, slender, and coarsely rugose ; the prothorax narrowed 

 anteriorly into a kind of neck, the mesothorax narrower than 

 the pro- or metathorax, the latter elevated and furnished with 

 two long, stout spines ; legs elongate and having a number of 

 erect, long hairs. Abdomen ovate; the node of the peduncle 

 elongated, incrassate and slightly bent, widest at the base. 



Hab. Brazil (Ega). (Coll. H. W. Bates.) 



