THE LAMARCKIAN PRINCIPLE 59 



neuters who then come to the front, and subsequent generations 

 cannot possibly inherit the acumen and resourcefulness that 

 result from such exercise of the faculties. 



Let us see how this difficulty has been met by Lamarckians. 

 The bees, they say, gained their skill before the division of 

 labour in the hive was carried so far, before all the egg-laying 

 was done by one female only, at a time when each female not 

 only worked but also produced offspring. But is it not reason- 

 able to suppose that the improvement in skill has gone on hand 

 in hand with the division of labour ? And surely the same 

 principle to which the development of this skill is due must 

 now be maintaining it. If practice has produced results so 

 extraordinary, how does it happen that there is no deteriora- 

 tion, though for an enormous succession of generations the 

 parents, male and female, have given up all practice of the 

 art ? 



I shall now select from insect life two or three examples of a The ski 

 most wonderful phenomenon. Some insects have once only in 

 their lives to do work that requires the utmost skill. When a 

 caterpillar has grown to his full size it is time for him to make a 

 chrysalis, and if he does not make a really good one he has little 

 chance of ever emerging as a butterfly or moth. Some cocoons 

 are spun in an extremely clever way and the point which I wish 

 to lay stress upon here is that the skill cannot be the inherited 

 result of practice. Once and once only does the caterpillar try 

 his hand at such work and very beautifully he does it. There 

 are now at the Insect House at the Zoological Gardens some 

 cocoons spun by the caterpillar of the Rhodia fugax moth from 

 Japan. The top is left slightly open so that the moth may be 

 able to escape. And, presumably, since water might find its way 

 in at the aperture, a very neat little hole, that looks as if it were 

 hemmed round the margin, is made at the bottom for drainage 

 purposes. This at least I imagine to be the object. I mention 

 this because we are so familiar with the spinning of caterpillars 

 that we have become dulled to the wonder of the phenomenon. 

 The little speciality in the spinning of Rhodia fugax reawakens 

 us and enables us to realise the cleverness, if that word is suit- 



