INADEQUACY OP NATURAL SELECTION, ETC. 683 



structures and habits of which show that they have all descended 

 from a common ancestor, some species have winged females and 

 some wingless females ; and that though they have lost the wings 

 the ancestral females had, these wingless females convey to the 

 males the normal developments of wings ? Or, still better, how 

 is it that in the Psychidce there are apterous worm-like females, 

 which lay eggs that bring forth winged males of the ordinary 

 imago form ? If for males we read workers, the case is parallel 

 to the cases of those social insects, the queens of which bequeath 

 characteristics they have themselves lost. The ordinary facts of 

 embryonic evolution yield us analogies. What is the most com- 

 mon trait in the development of the sexes ? When the sexual 

 organs of either become pronounced, the incipient ancillary organs 

 belonging to the opposite sex cease to develop and remain rudi- 

 ments, while the organs special to the sex, essential and non- 

 essential, become fully developed. What, then, must happen 

 with the queen-ant, which, through countless generations, has 

 ceased to use certain structures and has lost them from disuse ? 

 If one of the eggs which she lays, capable, as Professor Weis- 

 mann admits, of becoming queen, male, or worker of one or other 

 kind, does not at a certain stage begin actively to develop its re- 

 productive system, then those organs of the ancestral or pre-social 

 type which the queen has lost begin to develop, and a worker 

 results. 



Another difficulty in the way of my view, supposed to be fatal, 

 is that presented by the Honey-ants aberrant members of certain 

 ant-colonies which develop so enormously the pouch into which 

 the food is drawn, that the abdomen becomes little else than a 

 great bladder out of which the head, thorax, and legs protrude. 

 This, it is thought, cannot be accounted for otherwise than as a 

 consequence of specially endowed eggs, which it has become 

 profitable to the community for the queen to produce. But the 

 explanation fits in quite easily with the view I have set forth. 

 No one will deny that the taking in of food is the deepest of 

 vital requirements, and the correlative instinct a dominant one ; 

 nor will any one deny that the instinct of feeding young is less 

 deeply seated comes later in order of time. So, too, every one 

 will admit that the worker-bee or worker-ant before regurgitat- 

 ing food into the mouth of a larva must first of all take it in. 

 Hence, alike in order of time and necessity, it is to be assumed 

 that development of the nervous structures which guide self 

 nutrition, precedes development of the nervous structures which 

 guide the feeding of larvae. What, then, will in some cases 

 happen, supposing there is an arrested development consequent 

 on innutrition ? It will in some cases happen that while the 

 nervous centres prompting and regulating deglutition aro fully 



