William Morton Wheeler 
The Social Insects [PDF ebook] 
Their Origin and Evolution

Originally published in 1928, this volume, by a world authority on the subject, sums up our knowledge of the social insects. It inquires what are the social insects and what it is that makes us call them ‘social’. Terebrantia, aculeata, wasps, bees, ants, and termites are discussed in a succession of chapters, showing how they have evolved, to how great an extent they have developed, and what are the peculiarities of their evolution. Polymorphism, the Social Medium, Guests and Parasites of the Social Insects, are other subjects discussed in this fascinating book.