208 



mesouotuui subequal in length, the former moderately broad, 

 convex, the latter viewed from the side somewhat cylindrical and 

 sloping backwards from the pro-mesouotal suture, this latter and 

 the meso-metanotal suture distinct ; metanotum more or less 

 raised, convex and gibbous, obliquely truncate posteriorly ; legs 

 long, robust, the calcaria pectinate, the claws simple. Node of 

 the pedicel upright or slightly inclined forward ; abdomen short, 

 broadly oval, not produced anteriorly so as to overhang the 

 pedicel. 



Key to the Species. 



a. Head viewed from the front not emarginate 



posteriorly. 

 a'. Thorax "in profile widely emarginate at the 



meso-metanotal suture '. I. anceps, p. 298. 



V. Thorax in profile not emarginate at the meso- 

 inetanotal suture ; meso- and metanotum 



level one with the other /. glabef, p. 299. 



l>. Head viewed from the front widelv emarginate 



posteriorly ." /. lavigatus, p. 299. 



338. Iridomyrmex anceps, Roger (Formica), Berl. ent. Zeit. \ii 

 (18< 3 3), p. 164, ; Forel, Jour. Bomb. N. H. Soc. ix (1895), 

 pp. 468 & 469, $. 



. Head, thorax and abdomen dark castaneous brown, with a 

 beautiful metallic refulgence in certain lights ; antennae very much 

 and legs slightly paler reddish brown. Pilosity very sparse, con- 

 fined to a few scattered pale hairs chiefly on the front of the head 

 and apex of the abdomen. Pubescence fine and silky, tolerably 



Fig. DO. Iridotiiyrmex aiiceps, ^. 



abundant, especially on the abdomen. Head with the mandibles 

 triangular, very much longer than broad, cheeks slightly convex ; 

 mandibles elongate, the masticatory and outer margins nearly 

 equal ; clypeus triangular, nearly flat, almost as high as broad ; 

 the front with a distinct but short vertical carina between the 

 antennal carinae; eyes placed laterally and a little forw ard, closer 

 to the top of the head than to the anterior margin. Thorax 

 elongate, narrow, the metanotum remarkably raised and forming 



