HYMENOPTERA. 113 



pate, with a large curved tooth at about half their length within ; 

 the labial palpi 2-jointed ; the maxillary palpi 2-jointed ; the 

 antenme slender and 11-jointed. Thorax elongate, constricted 

 in the middle ; the legs slender and elongate. ' The node of the 

 peduncle of the abdomen incrassate, elongate and narrow ; the 

 segments of the abdomen very slightly constricted. 



The Ants belonging to this genus are those known as the 

 " Driver and Visiting- Ants of Africa." An interesting account of 

 their habits is published in the ' Transactions of the Entomo- 

 logical Society.' They are described as marching in vast armies, 

 driving everything before them capable of muscular motion, so 

 formidable are they from their numbers and bite : in respect to 

 that fact they stand unique in their habits, and in distinction 

 from other species. Their sallies are made in cloudy days and 

 in the night, chiefly the latter : an exposure to the direct rays of 

 the sun is almost immediately fatal. If they should be detained 

 abroad till late in the morning, on a sunny day, by the quan- 

 tity of their prey, they construct arches over their path ; but 

 should their way run under thick grass, &c., affording sufficient 

 shelter, the arch is dispensed with. Whenever a stream of water 

 intercepts their course in their excursions and migrations, if it 

 should not be extensive, they compass it ; but if otherwise, they 

 make a line or chain of one another, gradually extending them- 

 selves by numbers across, till a connexion is formed with the 

 opposite side, and thus a bridge is constructed, over which the 

 main body passes in safety. The Drivers delight in rather low 

 localities, generally the base of hills; consequently they are 

 liable to be driven from their haunts during the rainy season, 

 when the violent and continued rains, and the sudden swelling 

 of rivers, cause the low grounds to be overflowed. In such an 

 emergency, they throw themselves into a rounded mass, deposit 

 their pupae and eggs in the centre, and thus float upon the water 

 till a place of safety is reached, or the flood subsides. Their 

 entrance into a house is soon known by the simultaneous and 

 universal movement of rats, mice, lizards, cockroaches, &c., and 

 of the numerous vermin that infest dwellings, which renders 

 their visits sometimes desirable. The mandibles of the Driver- 

 Ant of the largest size are formidable, strongly hooked, having 

 one tooth ; those of the second size are flatter, sharper, and 

 armed with strong teeth ; the edges are finely serrated, and 

 admirably calculated for lacerating and cutting muscular fibre. 

 The inhabitants of the negro villages are frequently obliged to 

 abandon their dwellings, taking with them their children, and wait 

 until the ants have passed. 



The males and females of Anomma are not known. 



