26o THE BIOLOGY OF INSECTS 



cuticle, while membranous areas of the thorax grow out 

 into bladder-like or finger-like processes (exudatoria). This 

 curiously degenerative condition, due to overgrowth of the 

 fat-body, brings the beetles into direct feeding relation with 

 their termite hosts, as the insects can all obtain and swallow 

 exudations from each others' swollen bodies. It is note- 

 worthy that the larvae of these " termitophile " rove- 

 beetles (Fig. 65, a) are of a primitive relatively long-legged 

 insectan type, resembhng in aspect the young termites 

 (Fig. 64, a) whose quarters they share. Very remarkable 

 among the termites' guests are certain abnormal flies 

 (Diptera) like the beetles with swollen abdomens and with 

 their wings reduced to strap-like vestiges. Of these the 

 African and Indian Termitoxenia and Termitomyia are 

 described by Wasmann (1900), the African Ptochomyia 

 (1920) and the Brazilian Termitomastus (1901) by F. Sil- 

 vestri. These are clearly related to well-known families 

 of Diptera (Phoridae and others), of normal structure and 

 with well-developed wings, but all have undergone degenera- 

 tive modification in correspondence with their dependent 

 life in the termites' nests. Wasmann beheves that in 

 Termitoxenia the larval and pupal stages have been elimi- 

 nated from the life-histor}^ and that an imago is hatched 

 from the egg. 



Early in this chapter (p. 218) it was suggested that in 

 an advanced insect community the individuality of the 

 single bee or ant might be regarded as merged in a greater 

 individuality of the society. This view has been forcibly 

 advocated by Julian Huxley (19 12) in a general discussion 

 on the Individual in the Animal Kingdom. '' Communities 

 of ants and bees are," according to him, '* undoubted in- 

 dividuals " ; the single insects are so modified as to exhibit 

 a differentiation of structure and function corresponding to 

 the " division of labour " among the organs of an animal 

 body ; one single ant or bee apart from her comrades is 

 incapable of prolonged survival, and owing to the develop- 

 ment of the insectan nervous system the ant society is *' an 

 individual . . . whose parts, though not contiguous in space, 



