MEXICAN FORMICIDyE. 887 



neck. Clypeus truncate behind, slightly arcuated ante- 

 riorly and slightly emarginate at the middle. Mandibles 

 with two large and acute teeth at the apex, the rest finely 

 denticulate. Antenna very long and slender, the scape 

 about twice as long as the head. Thorax much elon- 

 gated, the prothorax elongated pyriform, broadest behind 

 and with a neck-like constriction anteriorly; it is convex 

 above and at the sides; transverse mesonotal depression 

 quite strong, extending down to the lateral margin, the 

 posterior half sloping gently and uniformly to the meta- 

 notum; meso-metanotal constriction somewhat stronger 

 than that of the mesonotum. Metanotum elongated and 

 gently curved towards the base of the first node, the 

 basal section much longer than the declivity; declivity 

 slightly concave along the middle; the thorus very mi- 

 nute. Second node subglobose. 



Head finely and densely shagreened, the space between 

 the frontal carina smooth; clypeus faintly granulated. 

 Mandibles sparsely punctured. Pro- and mesonotum 

 finely and densely shagreened, the metanotum granu- 

 lated. Nodes apparently smooth. Abdomen smooth, 

 the basal half or more finely shagreened. Erect hairs 

 sparse and slender, shorter and suberect on the scape 

 and legs; appressed pubescence very minute and sparse. 



Color yellow; the mandibles and legs slightly paler, 

 the abdomen faintly brownish. Eyes black. The whole 

 surface polished. . 



Sixteen soldiers and numerous workers. Cape Re- 

 gion, Sierra San Lazaro. 



This form differs from Ph. susanncB in the somewhat 

 larger size, longer antenna, shallower transverse depres- 

 sion and not abrupt posterior half of the mesonotum, the 

 less deep meso-metanotal constriction and the longer met- 

 athorax. 



