A Monograph of the Formicidae of South Africa. 403 



TiiiBE CATAULACINI. 



Catauxacus inteudens, Smith, var. intermeditjs, Santschi. 

 Ann. Soc. Ent. France, vol. 85, p. 287, £, 1916. 



" $ . 4 - 2-4 - 5 mm. long, tlie head deflected. Dull. Sculpture a 

 little stronger than in intrudens, Smith, but much less pronounced 

 than in rugosus, Forel, and C. Bequaerti, Forel. The rugae on the head 

 are further apart (about 13 between the eyes), and the transverse 

 rugae form a more distinct reticulation. The declivity of the epinotum 

 (apart from a few transverse striae between the spines) and the 

 anterior face of the 1st node are smooth. The longitudinal sulci on 

 the petiole more regular. The abdomen punctured, also fairly sharply 

 striate at the base and slightly so at the apex. Pilosity white, 

 intermediate in quantity and length between G. Bequaerti and intru- 

 dens. Head a little less narrowed in front than in intrudens, more 

 than in Bequaerti, relatively smaller than in those two species, with 

 the hind margin straight. Thorax as elongate as in Bequaerti, but 

 with the sides dentate as in intrudens. ' The spines are closer together, 

 more clearly parallel and as acute as in intrudens. First joint of the 

 petiole subcorneal as in the latter species, with the upper face smooth 

 and very oblique in front. Second joint as wide as the 1st, with 

 a fairly distinct median groove on the anterior and upper faces. 

 Abdomen a little less convex than in intrudens, a little more than in 

 Bequaerti. Colour as in those species." 



Bembesi, S. Rhodesia. (S.A.M., E.M., Gr.A. colls.) 



Genus CATAULACUS. 



I have endeavoured to draw up a key to the six forms which I have 

 seen, but in view of the trifling distinctions on which authors have seen 

 fit to erect new species in this genus, too much reliance should not 

 be placed on it. In fact, a review of these six forms leads me to the 

 belief that we have only two nuclei of species, one of which is G. 

 micans, Mayr, with durbanensis, Forel, Lujae, Forel, and Marleyi, 

 Forel, more or less intimately associated with it, and the other G. 

 Baumi, Forel, with its allied forms, batonga, Forel, bulawayensis, Forel, 

 and intrudens var. intermedius, Santschi. 



v 

 Key to the £ £ Gataulacus. 



(10). 1. Head clearly narrowed in front of the eyes. 

 (7). 2. Base of abdomen only feebly striate longitudinally. 



26 



