A Monograph of the Formicidae of South Africa. 171 



(35). 11. Antennae with 11 joints or less. 



(20). 12. Antennal scrobes present. 



(14). 13. The antennal scrobe lies below and external to the eye ; posterior 



angles of the head more or less'prolonged and denticulate. Epinotum 



armed. Antennae 11- jointed . . . Cataulacus, Smith. 



(13). 14. The antennal scrobe lies above the eye ; posterior angles of the head 



not prolonged and denticulate. 

 (18). 15. Pro- and mesonotum more or less distinct, not forming a single 



piece which overhangs the epinotum. 

 (17). 16. Antennae 11-jointed 



(16 b). 16 a. Hairs simple .... Xip homy rmex, Forel. 



(16 a). 16 b. Hairs spatulate ..... Dicroaspis, Emery. 

 (16). 17. Antennae 10-jointed . . Sub-genus Decamorium, Forel. 



(15). 18. Pro- and mesonotum more or less fused into a single disc, the poste- 

 rior margin of which overhangs the epinotum. Antennae 9- join ted. 



Meranoplus, Smith. 

 (12). 20. Antennal scrobes absent. 

 (22). 21. First joint of all the tarsi, or at least of the anterior or the posterior 



tarsi greatly enlarged, as wide as the tibiae. Thorax without trace 



of sutures. Antennae 6-jointed . . Melissotarsus, Emery. 



(21). 22. First joint of the tarsi simple, not enlarged; antennae with more 



than 6 joints. 

 (24). 23. Antennae 7- jointed . . . Myrmicaria, Saunders. 



(23). 24. Antennae with more than 7 joints. 

 (30). 25. Antennae 11-jointed. 

 (29). 26. Epinotum unarmed or at the most feebly bituberculate. $ $ usually 



monomorphic. 

 (28). 27. Clypeus bicarinate, or with carinae at least faintly indicated. 



Monomorium, Mayr (part). 

 (27). 28. Clypeus without carinae .... Diplomorium, Mayr. 

 (26). 29. Epinotum bidentate; £ $ strongly dimorphic, the y. % with very 



large elongated heads .... Aneleus, Emery. 



(25). 30. Antennae with less than 11 joints. 

 (32). 31. Antennae 9-jointed ( $ 13-jointed, ? 10-jointed). £ $ very small, 



$ and ? enormously larger than the £ Carebara, Westwood. 



(31). 32. Antennae 10-jointed. 

 (34). 33. Dimorphism of the £ £ but slightly marked, or if not, the head of 



the £ major is subquadrate or broader than long. 



Solenopsis, Westwood. 

 (33). 34. Dimorphism of the £ £ strongly marked ; head of the £ major (%) 



elongate ...... Aeromyrma, Forel. 



Antennae 12-jointed. 



At least some of the hairs on the body spatulate. 



Calyptomyrmex, Emery. 



Hairs on the body not spatulate but simple, or trifid (most species of 



Triglyphothrix), or slightly clavate (Leptothorax). 



First node of petiole bidentate or bispinose above. 



Atopomyrmex, Andre. 



First node of petiole simple. 



(11). 



(37). 



35. 

 36. 



(36). 



37, 



(33). 



38. 



(38.) 



39, 



