EDITOR'S INTRODUCTION 



When I decided to undertake the editing of this series of 

 volumes, I had a perfectly definite idea in mind. Biological 

 science has been of late years growing and expanding at a 

 prodigious rate. As a result, teachers of zoology and also of 

 botany — but I shall confine myseff to Animal Biology — have 

 had to face the gravest difficulties in regard to their curriculum. 

 The first difficulty is a purely quantitative one : now that the 

 subject has invaded so many new fields, how to stuff this 

 tenfold bulk of knowledge into the brains of students in the 

 same time as before. The second difficulty concerns the 

 relative value of the different biological disciplines. Shall 

 Comparative Morphology continue in the future to dominate 

 the undergraduate's learning period, with Genetics, Cytology, 

 Entwicklungsmechanik, Animal Behaviour, Systematics, Dis- 

 tribution, Ecology, Histology, Comparative Physiology, and 

 Evolution tacked or thrown on here and there like valances or 

 frills or antimacassars ? or can it and should it renounce its 

 pretensions and become one of a society of equals ? 



It is to my mind more important to attempt an answer to 

 this second question first. I do not believe that comparative 

 morphology has the right to demand the lion's share of the 

 students' time and energy. That it at present obtains that 

 lion's share is due almost entirely to historical reasons — to the 

 fact that zoological departments grew up while comparative 

 anatomy and morphology were the most fruitful and the most 

 interesting lines of attack in zoology. 



Those who uphold the present system tell us that morph- 

 ology is the foundation of zoology, the backbone of the subject, 

 and that it is impossible or unprofitable to embark on subjects 



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