134 LIFE STORIES OF AUSTRALIAN INSECTS. 



workers are further specialised to form (a) soldiers, 

 (b) nest workers. The latter are sometimes 

 smaller in size than the soldiers, example the sugar 

 ant (Camponotus nigriceps). In other species there 

 is practically very little difference in size between 

 the workers and soldier-workers — example : 

 greenheads (Ectatomma metallic um). The 



workers are wingless, and either have a sting or an 

 ejaculatory organ from which formic acid can be 

 ejected. Upon them devolves the whole care of the 

 nest. Workers are aborted females. It is because 

 of this variety of type in the female ants that the 

 name heterogyna is given to the group, for there are 

 queens and workers, and the latter are often spec- 

 ialised into soldier workers and nest workers. 



Formation of a Colony. 



When the time has come for the founding of 

 new colonies, males and females are hatched in the 

 old nest, and on some very warm evening the males 

 and females prepare to set out on the "marriage- 

 flight." There is great excitement in the nest, and; 

 the workers rush about and accompany the depart- 

 ing males and females to the door of the old home 

 to see them start off. After this nuptial flight 

 the fertilized females drop to the ground, cut 

 off their wings, and each seeks a place to 

 start her new home. But a large number of these 

 queens are seized by waiting insect enemies, and the 

 males also fall victims to insects and birds, or drop 

 into water. 



We will follow the recorded life history of a queen 



