a TEANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



will long preserve it as a masterpiece of popular exposi- 

 tion of science. Yet every chapter seems far from us 

 as a bygone age; its pages are alive no longer. How 

 h-as this come about ? The facts are true, and therefore 

 living as ever ; the style is classical, and therefore never 

 dying. It is the point of view that has suffered change. 

 The question asked throughout is the question that it 

 was the fashion at that time for biologists, and especially 

 anatomists, to ask and to attempt to answer. It was of a 

 phase that was passed through by such students at the 

 period of the " encyclopedists " and of Kousseau, and 

 lingered for a generation longer. The question asked was 

 one beyond the limit of regions accessible by the means of 

 enquiry that obtains in natural philosophy. It is now 

 generally acknowledged that this kind of teleology lies 

 beyond the province of biology. We desire not to trespass 

 across that limit. We are content to struggle with a 

 humbler problem. The question why ? is not answered 

 by positive science, but only the question how ? and some- 

 times the question how much ? The physiologist cannot 

 say why a muscle contracts, nor define '"life." To dog- 

 matise concerning the "why" of a bird's flight, implies 

 the knowing the " why" of the bird's existence. We may 

 be able to see how things have happened, or how they 

 will happen ; and it is a first step in the acquisition of 

 positive knowledge to know that the ratio rei is not the 

 " reason why." To confuse natural science with meta- 

 physics is a mischievous mistake for the enquirer, at 

 least for the present and for some centuries to come. 



At first sight, function seems in many instances more 

 obviously related to morphological structure than is borne 

 out by a more searching examination of the two. Es- 

 pecially do writings upon mammalian anatomy furnish 

 numerous examples of the looseness of the logic that is 



