INSTINCT OF INSECTS. 



409 



For the sake of distinctness and compression, I have con- 

 fined myself in considering the numbers of the instincts of 

 individual insects to a single species, the bee ; but if the his- 

 tory of other societies of these animals — wasps, ants, &c. 

 detailed in my former letters, — be duly weighed, it will be 

 seen that they furnish examples of the variety in question 

 fully as striking. These corroborating jDroofs I shall leave to 

 your own inference, and proceed to the third head, under 

 which I proposed to consider the instincts of insects — that 

 of their extraordinary development. 



The development of some of the instincts of the larger 

 animals, such as those of sex, is well known to depend upon 

 their age and the peculiar state of the bodily organs ; and to 

 this, as before observed, the succession of different instincts 

 in the same insect, in its larva and perfect state, is closely 

 analogous. But what I have now in view is that extraordi- 

 nary development of instinct which is dependent not upon 

 the age or any change in the organisation of the animal, but 

 upon external events — which in individuals of the same 

 species, age, and structure, in some circumstances slumbers 

 unmoved, but may in others be excited to the most singular 

 and unlooked-for action. In illustrating this property of in- 

 stinct, which, as far as I am aware, is not known to occur in 

 any of the larger animals, I shall confine myself as before to 

 the hive-bee; the only insect, indeed, in which its existence 

 has been satisfactorily ascertained, though it is highly pro- 

 bable that other species living in societies may exhibit the 

 same phenomenon. 



Several of the facts occurring in the history of bees might 

 be referred to this head ; but I shall here advert only to the 

 treatment of the drones by the workers under different circum- 

 stances, and to the operations of the latter consequent upon 

 the irretrievable loss of the queen — facts which have been 

 before stated to you, but to the principal features of which 

 my present argument makes it necessary that I should again 

 direct your attention. 



If a hive of bees be this year in possession of a queen 

 duly fertilised, and consequently sure the next season of a 



