PROPHETIC INSTINCT OF FOSSOR ir 9 



The wasp-like insect has no opportunity of learning by 

 experience, because it can never know whether the larva 

 stored up is a failure or a success. If the larva had not 

 been stung, or, accepting the received accounts, had been 

 stung in the wrong place, it would struggle and perhaps 

 kill the young grub ; or, dying of starvation, it might dry 

 up and be useless as food. But the Hymenopteron never 

 goes back to inquire. It makes all the difference to the 

 young grubs whether the food provided for them is in an 

 appropriate condition or not, but it makes no difference 

 whatever to the parent insect. The latter seals up the 

 chamber in which its eggs have been laid and never 

 opens it again ; it has no chance of noting the failure or 

 success of the food it has provided. It is clearly a case, 

 like that of the cocoon, which cannot be explained on the 

 Lamarckian Theory and must be explained on the Dar- 

 winian. And this latter interpretation is easy: those 

 insects which possessed the nervous mechanism impelling 

 them to provide food in an appropriate condition gave to 

 their offspring the opportunity of surviving and inheriting 

 the same instinct ; while others, impelled to perform less 

 efficient actions, were thereby cut off from any representa- 

 tion in the next generation. 



If the origin of wonderful and complex examples of 

 instinct such as these cannot be explained by the La- 

 marckian Theory but readily by the Darwinian, why 

 should not Natural Selection also offer an adequate 

 explanation of all other cases ? 



I have already taken up a great deal too much of your 

 time. I hope to have the opportunity to-night of hearing 

 stronger arguments in favour of the Lamarckian Theory 

 than it has been my opportunity to meet hitherto. 



Note. — In revising the shorthand transcript for publication, I have 

 not made any changes which alter the character of the address. It 

 remains the record of a spoken address, the sequence and continuity 

 of which were maintained by the use of brief notes. I have not verified 

 the quoted opinions and words of others, and there are probably verbal 

 errors. I believe, however, that in every case the true meaning of the 

 author has been preserved. 



Oxford, May 21, 1894. 



