4 Canadian Record of Science. 



structure ; we are really observing the mode in which 

 evolution, that is modificatiou of structure, has taken place. 



iSTow it is surprising how few accurate observations we 

 have on the relation of animals to their environment. 

 The older naturalists were content, as I have said, to 

 classify, interspersing here and there some remarks as to 

 habits, which were generally erroneous. Yet there are 

 few subjects of study more important to zoology. Some 

 of the most fundamental questions in the science depend 

 for their solution on such studies. Chief among these is 

 the amount of weight to be assigned to the principle 

 which was regarded by Darwin as the driving power 

 of evolution, viz., natural selection. 



I need hardly remind you that by natural selection 

 is meant the theory, that the struggle for existence, which 

 inevitably follows from the tendency of every species 

 of animal to produce far more young than can possibly 

 survive, will select survivors with some advantageous 

 peculiarity, which peculiarity will, in this way, become a 

 character of the species. 



Now, when stated in these broad, general terms, few 

 would deny the truth of the theory, and certainly when 

 we examine the larger differences which separate families 

 and orders from each other, we can often show their 

 relation to differences in surroundings and habits, but the 

 question at issue is whether the minute differences which 

 separate species from species can be so explained. High 

 authorities have taken opposite sides on this question, 

 and it can only be settled by systematic open air study. 

 If the marks of species are not so to be interpreted, then 

 we want to know what is their explanation, and, above 

 all, what keeps allied species from intermingling. 



The first duty of a Natural History Society is to 

 prej^are an accurate list of the species of animals fr(jm the 

 surrounding country. I am well aware that our Society 

 has done this in several groups of the animal kingdom, 



