— 235 — 



a median longitudinal groove. Petiole and postpetiole similar to those 

 of the worker , but the former segment without posterior teeth. 

 Genitalia extruded. Legs slender. 



Plead opaque and finely punctate. Remainder of body shining; 

 pronotum sparsely punctate. 



Hairs reclinate, longer and much more abundant than in the 

 worker. 



Piceous black, legs brown: antennae and genitalia whitish, 

 valves of the latter tipped with brown or black. Wings grayish 

 hyaline, with pale veins and stigma. 



Numerous specimens from Jalapa. 



Except in color this species agrees so «-.losely with Mayr's 

 description of C. forni osa that T have decided not to describe it 

 as a distinct species, although I am unable to find anything like 

 it among the various tropical New World species, many of which 

 are represented in my collection. Mayr's foì-mosa seems not to 

 have been recognized by subsequent observers , although it was 

 taken in Mexico. 



17 — Megaloinyrmex silvestrii sp. nov. 

 Worker. Length 3.5-4 mm. 



Head) excluding the mandibles, considerably longer than broad, 

 as broad behind as in front, with subparallel sides and rounded 

 posterior corners; occipital border with a distinctly raised edge. 

 Eyes large, with impressed orbits, a little in front of the middle 

 of the head. Mandibles rather weak and flat, with minutely den- 

 ticulate blades and only two teeth, wich are small and apical. 

 Clypeus convex in the middle, with rounded anterior border, 

 feebly and sinuately notched in the middle. Antenna! scapes exten- 

 ding about V3 their length beyond the posterior corners of the 

 head; club 3-jointed, first and second funicular joints longer than 

 broad, joints 3-8 as broad as long. Pro and mesonotum forming 

 a single hemispherical mass, without a depression at the promes- 

 onotal suture. Mesoepinotal depression broad and very deep, owing 

 to the peculiar structure of the epinotum, which is raised to form 

 a prominent rounded ridge on each side terminating at the an- 

 terior border of the segment in an ear-like lobe. These ridges run 

 down onto the declivity of the epinotum , and are separated by 



