DEVELOPMENT OF SEX IN SOCIAL INSECTS. 39 



but as a rule they are scarce in such places, they lay fewer eggs, 

 probably, but certainly " dwarf races " of insects can be " produced by 

 partial starvation during the course of development." The Professor 

 leaves out of account how long natural selection has been teaching 

 the ants and bees the minimum of food which will not endanger their 

 working power, and yet not develop their reproductive organs beyond 

 a certain point. One brood of flies and butterflies is of but little 

 service for generalisation, or for comparison with times or ages like 

 these, in fact it is the poverty of the Professor's facts which must 

 astonish the practical naturalist, who deals with things rather than 

 theories. Truly we agree with the Professor that "we cannot seriously 

 suppose that these larvte are really insuiKciently nourished and kept 

 small by hunger," and we also agree that they get " exactly as much 

 nourishment as they need for the development of the worker-type and 

 as their instinct demands for the time when they have become 

 worker-larvae, owing to the poorer food." But this we venture to think 

 is not due to the presence of any special "id," so much as to a 

 response in the larval organism itself to this particular condition of 

 environment, which response natural selection has, in the course of 

 ages, bred into it, and yet, in the face of the fact that, as the Pro- 

 fessor tells us, " the worker-larva is a distinct individual, with its own 

 particular tendencies and instincts, just as much as is the full-grown 

 worker," and that "bee larvae all receive similar food for three days only, 

 and thus long they are undifferentiated," we are to suppose that it is 

 some peculiarity of the germ-plasm Avhich settles the final development, 

 and not the reaction of the larva to a stimulus directly applied in the 

 way of food, the reactions due to which are palpably plain to our 

 intelligence as a matter of actual quantity. 



We quite agree with Weismann as to the remarkable fact that "this 

 adaptation of the larval organism to the determining stimulus of a 

 specific mode of nourishment should be so perfectly similar in two 

 such different groups of insects as the bees and termites, for there 

 can of course be no doubt that it has arisen independently in each 

 group." The same result has been arrived at owing to the same 

 necessity, it is that part of the physical organisation which the com- 

 munity can reach which is affected. They can govern the food supply, 

 and a limited food supply having produced advantageous results to the 

 community, the particular line of producing the necessary modifica- 

 tions is persevered in. To us there is no necessity for considering the 

 germ-plasm of the worker egg to contain but one "id," which is capable 

 of development to any point extending between the most highly- 

 organised queen or the most lowly-organised worker ; that this power 

 exists even in the neAvly-hatched larva, and that then the stimulus of food 

 comes into play, both as determining the quantity and direction of the 

 development, natural selection having determined the normal limits 

 which shall produce the best organised queen-product, and the best 

 organised worker-product — best in the sense of their future require- 

 ments and work — but that they are two distinct forms of females, 

 with a separate ontogeny, the Professor's arguments have entirely 

 failed to convince us. 



