112 HYMENOPTERA. 



As already stated, the position of the Chrysididce is somewhat 

 uncertain ; they have affinities both with the Terebrantia and the 

 Aculeata. In certain genera of the Vespidce, especially Polybia, the 

 abdomen is so retractile that it can almost be drawn within the 

 first segment ; and this may indicate some relationship to the 

 retractile abdomen of the Chrysididce. 



HYMENOPTERA ACULEATA HETEROGYNA. 



FAMILY VIII. Formicidce. 



Social insects, consisting of males, females, and neuters; the 

 last wingless, and the two former only acquiring wings (which are 

 ample, but soon lost) for a single flight. 



The Formicidce, or Ants, may be divided into three sub-families ; 

 the Formicince, many of which bite sharply, but are stingless ; and 

 the Ponerince and Myrmicince, in which the females and neuters (or 

 workers) are generally armed with a sting. In the Ponerince the 

 petiole of the abdomen is formed of only one node, and in the 

 Myrmicince of two. The singular genus Dorylus, Latr., has been 

 formed into a separate family, Dorylidce, characterised by its fili- 

 form instead of angulated antennae, its small head, and long 

 cylindrical abdomen. But it is structurally nearest related to the 

 Ponerince, and without further observations on these exotic insects, 

 and their habits and transformations, it is perhaps better to treat 

 them as belonging to that sub-family. 



The largest of the European Formicince is Camponotus Hercu- 

 laneus, Linn., which measures about half an inch in length, and an 

 inch in expanse of wing. It is a smooth black ant, with the 

 thorax (or at least the metathorax), the base of the abdomen, and 

 the legs, more or less red. The wings of the males and females 

 are deeply tinged with smoky yellow. It is very common in many 

 parts of Europe and North America, but is not found in England. 

 It is a very courageous insect, and an ant-hill will sometimes 

 send out an army, and fight a pitched battle with a neighbouring 

 community of its own or another species. These are regular wars, 

 and not slave-hunting excursions, which are undertaken by several 

 species of ants, for the purpose of obtaining pupae of another 

 species, which are afterwards reared in their nests to do the work 

 of the plunderers, who are too lazy in some cases to do anything 

 but fight, and are so absolutely dependent on their slaves that 

 they cannot even feed themselves without their help. 



