452 bulletin: museum of comparative zoology. 



135. Daceton armigerum (Latreille). 



There were several colonies of this species in the grounds of the 

 Zoological Garden at Para, where workers were often seen on the 

 fences and trees. At Itacoatiara I found a very large colony nesting 

 in a hollow standing tree. 



136. Acanthognathus occllatus Mayr. 

 Plate 5, fig. 39. 



Female. (Plate 5, fig. 35). Length 3.5 mm. 



Head cordate; excluding mandibles, twice as long as broad, with 

 convex sides and deeply excised occiput. Eyes large, convex, situ- 

 ated at middle of sides of head. Ocelli small, convex, white in color. 

 Clypeus longer than broad, its anterior border truncate. Antennae 

 slender and short; the scape not attaining the occipital corners, bent 

 and slightly thickened distally; first funicular joint two and a half 

 times as long as broad; joints 3-9 scarcely longer than broad; last 

 two much longer than broad, the apical nearly twice the length of 

 penultimate. Mandibles nearly as long as head, slender, straight; 

 apex with two long subequal teeth and a shorter tooth. On the inner 

 side near the base is a curved process, which extends upward a little 

 past the base. This is bidentate at apex. Pronotum very narrow; 

 in profile flat. Mesonotum evenly rounded above and at sides. 

 Scutellum rounded. Epinotum with base and declivity subequal in 

 length, the angle bearing a pair of stout, acute spines. Petiole elon- 

 gate, slender, the node globular. Postpetiole subglobose, about as 

 large as the petiolar node. Gaster short and thick. 



Head in front somewhat shining; genae and occiput smooth and 

 shining. Mandibles finely punctate. Antennae and thorax sub- 

 opaque, the latter coarsely, rugosely punctate. Scutellum with five 

 feeble longitudinal carinae. Petiole, postpetiole, gaster, and legs 

 finely punctate, shining. 



Front of head and occiput, thorax, petiole, postpetiole, gaster, 

 legs, and antennal scapes pilose. 



Color ferruginous; the front of head, thorax, and gaster darkest, 

 legs lightest. 



Described from one female which was found with a solitary worker 

 beneath a board on the ground at Para. 



