PREFACE. vii 



observation and experiment, has sucti difficulty in diffusing 

 itself. 



The object of our little book is to remedy this serious 

 educational deficiency in those who are otherwise. enlightened. 

 It is therefore a work of vulgarisation. Certain scientific 

 men, too strictly confined within their own circle, and whose 

 horizon is bounded by the walls of their laboratories, pro- 

 nounce, with disdain, though unjustly, this term vulgar- 

 isation. To find the truth is surely a noble labour ; but what 

 is the value of the discovered truth, if care is not taken to 

 propagate it, to introduce it into the patrimony of general 

 knowledge ? 



On the other hand, it must be granted that the work of 

 popularising has been brought somewhat into disrepute by a 

 crowd of pseudo-scientific publications, the authors of which, 

 trusting too little to the intelligence of the reader, either 

 administer only an infinitesimal dose of science, or think 

 themselves obliged to dilute the main idea with a deluge of 

 light or pleasing words, sacrificing thus at once to the most 

 amiable and most dangerous of our national peculiarities. 

 Science only deserves its name upon condition of preserving 

 a somewhat austere nobleness. For our part we have taken 

 care not to rob science of that which constitutes its strength, 

 and for this we trust the reader will give us' credit. In our 

 opinion there is not a person of moderate intelligence who 

 wiU not be able, at the cost of a slight mental effort, to read 

 and comprehend this book ; and we think also that by such 

 a perusal of it, sufficiently clear and complete ideas of Biology 

 wUl have been imparted. 



This is not a polemical work, but rather an exposition 



