MEXICAN FORMICID^E. 89I 



Head, densely and finely granulated and longitudinally 

 reticulate-striate, the stride becoming obsolete towards the 

 occiput. Frontal area polished and with a median carina. 

 Median section of the clypeus indistinctly granulated, 

 with a median carina and a few anteriorly diverging stria, 

 the anterior margin coarsely punctured, giving it a ser- 

 rated appearance. Mandibles polished, coarsely and 

 rather sparsely striated and punctured. Entire thorax 

 densely granulated, the neck of the pronotum with a few 

 transverse striee; both nodes and the abdomen also dense- 

 ly granulated, and the first abdominal segment with a few 

 shallow and somewhat elongated depressions. Erect 

 hairs yellowish, rather stiff and quite dense, especially so 

 on the head and abdomen, intermixed quite evenly with 

 shorter, suberect, stiff hairs. Legs and antennge with ap- 

 pressed pubescence, intermixed with a few erect hairs on 

 the scape and along inner edge of femora. 



Color reddish -yellow, the legs paler; mandibles red- 

 dish, with the external margin and cutting edge, the an- 

 terior margin of the clypeus and the eyes black. 



Two specimens. Tepic. 



This form appears to be the connecting link between 

 Pheidole and Messor. 



40. APHyENOGASTER MUTICA n. Sp. 



Worker: Length, 5 mm. Head longer than broad, 

 slightly narrowest in front, rounded behind. Frontal 

 area oval and with a few longitudinal striae. Clypeus tri- 

 angular, arcuate in front and with a broad and somewhat 

 angular emargination at the middle. Mandibles armed 

 with three large teeth at the apex and a number of smaller 

 ones behind them. 



Prothorax about one -fourth narrower than the head, 

 very convex and with a short neck; the meso- and meta- 

 thorax narrower and nearly parallel; anterior half of the 



