The Beginning and End of Life 407 



caps natural selection, and makes its acceptance as the one 

 great cause of specific origin much more difficult. He 

 believes all instincts to have been produced by it, and his 

 confidence in that principle is so robust, that he does not 

 .hesitate to cite instances which may well stagger the faith 

 \i less devoted adherents. Thus he tells us (p. 93) : — 



* The queen-bee takes her nuptial flight only once, and yet how 

 lany and complex are the instincts and the reflex mechanisms which 

 )me into play on that occasion ! Again, in many insects the deposi- 

 ^on of eggs occurs but once in a lifetime, and yet such insects always 

 ilfil the necessary conditions with unfailing accuracy. ... It is 

 ^indeed astonishing to watch one of the Cynipidcje {Rhodites rosoe) 

 depositing her eggs in the tissues of a young bud. She first care- 

 fully examines the bud on all sides, and feels it with her legs and 

 antennae. Then she slowly inserts her long ovipositor between the 

 closely-rolled leaves of the bud, but if it does not reach exactly the 

 •right spot, she will withdraw and reinsert it many times, until at 

 length, when the proper place has been found, she will slowly bore 

 deep into the very centre of the bud, so that the eggs will reach the 

 exact spot — and here the necessary conditions for its development 

 alone exist. ... It is the same with the deposition of eggs in most 

 insects. How can practice have had any influence upon the origin 

 of the instinct which leads one of our butterflies ( Vanessa levana) to 

 lay its green eggs in single file, as columns, which project freely 

 from the stem or leaf, so that protection is gained by their close 

 resemblance to the flower-buds of the stinging-nettle, which forms 

 the food-plant of the caterpillars ? ' 



How, we may ask in turn, can natural selection have 

 produced so admirable a result by mere chance variation 

 in the collocation of the molecules of the germ-plasms of 

 a creature which before had them not ? 



It has of late been ascertained that the gall which is 

 found in plants punctured by the ichneumon-fly Cynips, 

 is not produced as was supposed by the effect of the 

 puncture itself. It is produced subsequently by the move- 

 ments of the larva which is hatched from the egg laid by 

 the Cynips when it effected the puncture. The presence 



