598 Annals of the South African Museum. 



teeth. Anterior margin of clypeus feebly convex. The scapes extend 

 beyond the hind margin of the head by a little more than one-fifth 

 of their length. Pronotum convex transversely, very little wider than 

 long. Pro-mesonotal suture not strong, meso-metanotal suture obso- 

 lete, the metanotal region being indicated only by the stigmatic 

 orifices. Mesonotum convex transvei sely, parallel-sided, as long as 

 wide. Meta-epinotal suture narrow and not deep. Dorsum of epi- 

 notum widening very little posteriorly, nearly as long as wide, fairly 

 convex above. The declivity is subvertical in its upper two-thirds, 

 its lower third forming a subhorizontal shelf. The brow of the 

 declivity rounded. Scale of petiole inclined very little forwards, wider 

 above than below, the dorsal edge feebly convex transversely, thick 

 and rounded from front to back. Abdomen elongate, two-thirds 

 longer than wide. Legs fairly long and slender. 



Sawmills, Umgusa River, S. Rhodesia. 



To the naked eye, this species bears a deceptive resemblance in 

 colour and movements to Monomorium bicolor, race nitidiventris. Like 

 that species it is exceedingly agile and forms a nest in loose sand, 

 surrounded by a low and more or less circular crater. It is tolerably 

 distinct from Trimeni and its var. karrooensis in form and sculpture. 

 Judging by the description alone, it resembles decolor Emery in sculp- 

 ture, but is larger, of a different colour, and has a different scale 

 and longer scapes. 



(S.A.M., R.M., G.A. colls.; type in my collection). 



P. (sub-gen. Anoplolepis) Macgregori, n. sp. 



§. 3 mm. Dark brown or blackish brown, the scape, basal half 

 of the flagellum, and the tarsi ochreous, tibiae ochreous brown, 

 mandibles ferruginous. The sculpture consists of a microscopic 

 punctate rugulosity, but nevertheless stronger than in Trimeni; dull 

 all over. Pubescence whitish on the head and thorax, greyish on 

 the abdomen, similar to that of Trimeni, but much less apparent on 

 the head and thorax. A few yellowish pilose hairs on the clypeus 

 and apical margins of the abdominal segments. Thorax narrower 

 and more convex transversely than in Trimeni. The mesonotum is 

 distinctly longer than wide, and the dorsum of the epinotum longer 

 than in Trimeni, or as long as the declivity. The scale of the 

 petiole is thicker, not emarginate as in Trimeni. Otherwise like that 

 species. Glenville, Bulawayo. Crawling on the trunk of a tree. 

 I specimen. 



Type in my collection. 



