NEW FORMICID^: FROM BARRO COLORADO ISLAND. 



169 



borders; the posterior corners rounded. Eyes small, feebly 

 convex, at the middle of the sides. Minute ocelli sometimes 

 present in large workers. Clypeus convex, its anterior border 

 broadly and evenly rounded. Frontal carinse short, parallel; 

 frontal area indistinct, convex in the middle. Mandibles rather 

 narrow and not very convex, 7-8 toothed, the apical tooth longer 



FIG. 5. Megalomyrmex (Cepobroticus) symmetochus sp. nov. a, head of worker, 

 dorsal aspect; b, thorax and pedicel of same, lateral aspect; c, head of male, dorsal 

 aspect; d, fore wing of female. 



than the others which are subequal, the most basal forming the 

 angle between the basal and apical borders. Maxillary palpi 

 3-jointed; labial palpi 2-jointed. Antennae robust, the scapes 

 extending less than one third their length beyond the posterior 

 corners of the head; funiculi thickened apically, but not forming 



