•460 Annals of the South African Museum. 



sparsely punctured. The epinotal spines are directed upwards and 

 slightly backwards, acute, hardly as long as their basal width. 

 The colour of the head is yellowish-red, without darker stripes, the 

 anterior margin darker than the rest. Otherwise like the type of the 

 species. 



It differs from the $ of spinulosa-nexa by the much shorter thorax, 

 and by the mesonotum, which is much more convex along the anterior 

 margin. The metanotum does not project over the epinotum, and the 

 dorsum of the latter is less deeply excavated. The dorsal edge of the 

 1st node is more feebly emarginate, and the dorsal face is as wide 

 in front as behind, not narrower as in spinulosa-nexa. The 2nd 

 node is narrower and the lateral teeth more obtuse, shorter and 

 somewhat flattened. The colour is also quite different from that of 

 nexa. 



<$ . 5 mm. Dirty ochreous yellow, the head black, the mesonotum 

 yellowish-brown, with a V- sna P e d yellowish band in front. Legs, 

 antennae and mandibles pale yellow. Head very closely and finely 

 reticulate-punctate, with a few rugae superimposed and radiating 

 from the ocelli. The latter are glassy yellow, large and very promi- 

 nent. Mesonotum sculptured more finely than in the $ . Eyes 

 occupying the anterior half of the head, ovoid, wider in front than 

 behind. Scutellum convex and gibbous behind. Dorsum of epinotum 

 fairly oblique, distinctly longer than the declivity, and as long as it is 

 wide. Second node of petiole widest behind, the sides moderately 

 angulated at the posterior third. Flagellum densely pubescent, the 

 scapes not extending back as far as the anterior ocellus. Seen from 

 in front the head is trapezoidal, widest anteriorly. Other characters 

 as in the type of the species. 



S. Rhodesia, fairly plentiful on the Forest Sandstone and Kalahari 

 Sand formations, but not occurring elsewhere as it is a distinctly 

 areniphilous species. The nest is very distinctive and like that 

 of the type-species ; it may be seen all along the railway line from 

 ISTyamandhlovu to the Victoria Falls. The entrance, of exceptional 

 width (from 1 to 2 in. in diameter), is surrounded by a wide but 

 low-walled crater. The area enclosed therein is kept perfectly smooth 

 and bare. As a rule, the entrance at about 4 or 5 in. from the sur- 

 face leads into a circumconical space from the bottom of which 

 galleries radiate outwards ; the central cone itself is pierced by a 

 vertical gallery which again leads into a second and lower circum- 

 conical chamber, similar to the upper one. (S.A.M., R.M., GT.A. 

 colls. ; types of $ and <$ in my collection.) 



