HYMENOPTERA PETIOLATA. 



771 



undergo a histolysis and are replaced by adipocytes.* The ants live upon 

 both animal and vegetable substances, and are very fond of sweet things. 

 The real eggs are very small. The structures commonly called ants' 

 eggs are the white, oval cocoons (case made by the larva). 



The eggs, which are laid in nests by one or more queens, give rise 

 to helpless larvae which are nursed and fed by workers. They are carried 

 from one part of the nest to another when occasion requires, and unlike 

 the Bees and Wasps they do not pass through their larval life in one 

 cell or chamber. They are fed from the mouths of the workers, with 

 semi-digested food. Some species form cocoons ; in others the pupae 

 are exposed. The pupae develop either into wingless forms, the workers 

 and soldiers, or into winged forms, the males and fertile females. The 

 queens are known to live several years. 



The nests of ants are not definite in shape nor are they formed largely of 

 wax or papery wood, but are irregular chambers connected by galleries 

 and usually subterranean. Some species form chambers in timber ; others 

 inhabit spaces in plants, which they are said to defend from the attacks 

 of leaf-cutting insects, etc. 



Some two thousand species are recognized. 



Sub-fam. 1. Camponotinae. The pedicel consists of one node ;. 

 poison gland a cushion of 

 convolutions underlying a 

 modified sting, which is 

 simply an ejaculatory orifice 

 for the poisonous fluid. This 

 family comprises the so- 

 called stingless ants, but 

 though they do not sting 

 they can eject a very poison- 

 ous fluid a considerable dis- 

 tance. There are some eight 

 hundred species ; Camponotus 

 is by far the largest genus. 

 .In some cases, at any rate, 

 when a new community is 

 being started, a single female 

 performs alone all the duties 

 of the nest. After the first 

 individuals, which are 

 workers, have emerged, she 

 becomes a true queen, per- 

 forming no function except 

 egg-laying ; all other duties 

 devolving henceforth upon 

 the workers. In the large 

 nests of the red-ant, Formica 

 rufa, many beetles and one 

 or two other ants live peace- 

 fully. F. sanguined, British, 

 makes slaves and servants 



FIG. 502. Aphaenogaster (Messor) barbarus. Al- 

 geria. A male ; B female winged ; C large 

 worker or soldier ; D small worker, x _!. 

 From Sharp. 



of F. fusca and F. cunicularia ; this habit is however carried to a 



* C. Janet, C. R. Paris, cxliv, 1907, p. 393. 



