A Monograph of the Formicidae of South Africa. 32i 



and the whole of the remaining segments of the abdomen smooth and 

 shining. Head subquadrate, widest across the eyes, wider than long 

 (excluding the mandibles), the sides convex, the posterior margin 

 straight, the posterior angles narrowly rounded. The eyes occupy the 

 anterior two-fifths of the head, not touching the base of the mandibles. 

 The latter very finely striate and dull, with 6 or 7 minute teeth. 

 Scapes long, as long as the 1st and 2nd joints of the flagellum taken 

 together, extending back as far as the posterior ocelli. The latter 

 small, not raised. Clypeus reticulate-punctate ; frontal area distinct, 

 frontal sulcus very shallow, shining, and extending back to the 

 anterior ocellus. Mesonotum twice as wide as long, and twice as long 

 as the scutellum. The parapsidal sutures and a median longitudinal 

 line between the Mayrian furrows smooth and shining. In profile 

 the dorsum and declivity of the epinotum form a continuous and 

 steep curve. Peduncle of the petiole thicker than in the $ , the node 

 thicker and shorter. The 2nd node like that of the '$ , but wider 

 and more narrowed in front. Wings tinged with dirty yellow, nervures 

 and stigma very pale yellow. 



A very distinct sj)ecies, easily recognised by the sculpture. It is 

 found only in the mounds of Platythyrea lamellosa-rhodesianaj usually 

 making its nest near the top and sides of the mound, or about 2 or 

 3 in. down below the entrance. Its association with Platythyrea is 

 probably an instance of what Wheeler has termed " xenobiosis." It 

 may be found in about 50 per cent, of the mounds of Platythyrea 

 in the Hillside district of Bulawayo, but I have never found it 

 elsewhere. 



(S.A.M., E.M., G-.A. colls.) ; types in my collection. 



T. longoi, Forel. 



Bull. Soc. Vaud. Sc. Nat., vol. 50, p. 344, $ , 1914. 



£> . 25-3 mm. Varying from brownish-yellow to dark yellowish 

 red- brown, the 1st abdominal segment brown, except at the extreme 

 base ; the posterior half of the head generally a little darker. Pubes- 

 cence almost entirely absent. The pilosity is fairly abundant, and 

 consists of short, thick, obtuse, and yellowish hairs, which are erect on 

 the body, oblique on the legs and scapes. Head and thorax fairly dull, 

 abdomen smooth and shining. Head strongly and longitudinally 

 rugose, with strong transverse anastomoses between the rugae, the 

 sides of the head more reticulate- rugose. Thorax reticulate-rugose, 

 the reticulations becoming gradually finer and closer posteriorly ; 1st 



