ANTS. 



aspects, the Formicid;e have also been called I leterogyna. All of the 

 species have retained in their development the four salient stages known 

 a^ the egg, larval, pupal and imaginal instars, which are peculiar to all 

 holometabolic insects. These stages and their relations to the- poly- 

 morphism of ants will he considered in subsequent chapters. In this 

 and the two following chapters I shall endeavor to give a rapid survey 



FIG. i. Camponotus americanus. (Photograph by J. (i. Hubbard and (). S. 

 Virgin queens and major and minor workers, natural size. 



of the external and internal anatomy, as these have become known to 

 us through the careful researches of a number of investigators, notably 

 Adlerz, Rerlese, Devvitz, Emery, Forel, Janet, Lubbock, ]\leinert and 

 Nassonow. 



The Segmentation of the Body.- There can be little doubt that the 

 ants are phylogenetically related, through the lower families of 

 Hymenoptera with the oldest and most primitive of all the existing 

 insects, the Blattoidea, or cock-roaches. Hut while the Blattoid body. 

 as seen, for example, in the common cock-roaches, is generalized, that 

 of the ants in its sharp demarcation of the head, thorax and abdomen 

 is highly specialized. These accentuated subdivisions enable anyone 

 to recognize an ant at a glance. In this respect the ants are the most 

 typical of insects, and may be the ones to which the terms IVTO^OV and 

 inscctitm were originally applied. While these and many other char- 

 acters make it seem a far call from the ant to its remote l>lattoid 

 ancestors, it must be borne in mind that the individual ant still passes 



