ANT AND TERMITE GUESTS 201 



Ants to that of the Termites, and have thereby become 

 new systematic species, since they, as a consequence 

 of their new mode of life, assumed characters by which 

 they approach the rest of the termitophil Aleocharinse 

 of the offensive type of the genera Discoxenus, Termito- 

 discus, Termitusa, Termitopsenius, etc. 



Since, in addition, Wandering Ants by preference 

 attack and plunder Termite nests and on such 

 occasions are also accompanied by their guesfcs of 

 the genera Doryloxenus and Pygostenus the first 

 riding on the Ants, the latter going on foot from 

 the biological standpoint it is also easily explained 

 how this transformation of originally dorylophil 

 species to a termitophil mode of life has been brought 

 about. 



(c) A third proof of the underlying principle of our 

 evidence is seen in the individual evolutional history 

 especially of Termitoxenia. This hemipterous genus 

 possesses, namely, peculiar staff-shaped dorsal growths, 

 which it is true stand on the site of former wings, but 

 are entirely useless for flight, while they serve various 

 other biological purposes, such as feeling organs, 

 transport organs by aid of the hosts, and as exudatory 

 organs. That, however, these enigmatical structures 

 were originally wings, that thus the wingless Termi- 

 toxenia have arisen from normally winged Diptera, can 

 still be shown to-day by the individual development 

 of these thoracic attachments ; since they still show, in 

 a certain youthful stage of the animal, the form of 

 wing flaps with a clear wing venation, which are later 



