A Monograph of the Formicidae of South Africa. 137 



gibbous, overhanging the pronotum ; scutellum gibbous ; epinotum 

 short. Legs slender, tibiae usually with a rudimentary calcar. 

 Petiole 1-jointed, transverse, flattened or excavated above. Abdo- 

 men cylindrical or clavate. Genital armature entirely retractile. 

 Stipes large, covering laterally the volsella ; lacinia very small. 

 Sub-genital plate forked, the branches linear, parallel and distant. 

 Unlike the species of the sub-genus Dorylus, the workers of this 

 genus do not so persistently avoid the light, and may be seen moving 

 about in the open, usually in files, even in the bright sunshine. 

 They are also far more nimble than those insects. Probably many 

 species live an entirely subterranean existence, but all the species 

 which are known to me from Ehodesia have been taken above the 

 surface of the ground. 



Key to the $ $ of the Genus Aenictus. 



V 



{4). 1. Third and 4th joints of the flagellum, or at least the 3rd, distinctly longer 



than wide. 

 (3). 2. Head distinctly wider in front than behind; dorsum of epinotum evenly 



and strongly reticulate-punctate eugeniae, Emery. 



(2). 3. Head not wider in front than behind, widest in the middle ; dorsum of 



epinotum unevenly and shallowly reticulate-punctate . . rotundatus, Mayr. 

 (1). 4. Third and 4th joints of the flagellum as wide as, or wider than long. 

 ■(6). 5. Head wider in front than behind in the £ major, parallel-sided in the 



5 minor mariae, Emery. 



'(5). 6. Head not wider in front than behind, workers monomorphic 



steindachneri, Mayr. 



Without having seen the species, it is not possible for me to 

 include rixator, Forel, in the above Key. It appears to differ from 

 the % minor of mariae, Emery, only in having 3 instead of 4 teeth 

 to the mandibles. 



A. eixatoe, Forel. 



In Emery, Bull. Soc. Ent. Ital., vol. 33, p. 48, $ , 1901. 



" $ . 1*9 mm. Mandibles narrow, their margins nearly parallel, 

 ■shining, feebly striate and armed with 3 teeth. Frontal carinae 

 short, fused together posteriorly. Head rectangular, as wide behind 

 as in front, feebly emarginate behind, and one-fifth longer than wide. 

 'The scape hardly reaches back to the posterior two-fifths of the 

 head, thickened along the apical two-thirds. Third to 6th joints 

 of the flagellum wider than long. Meso-metanotal suture forming 

 a distinct impression, but not constricted. Dorsum of epinotum 

 eonvex in the middle, the declivity triangular, margined by a 

 distinct ridge. Nodes of the petiole longer than wide, the 1st 

 joint longer and a little wider than the 2nd, having below and right 



