X EDITOR^S INTRODUCTION 



like comparative physiology or developmental physiology or 

 ecology until the student has gained a general knowledge of 

 the main types of the animal kingdom. I am quite prepared 

 to admit that morphology is the backbone of zoology. On 

 the other hand, I am not at all sure that it is the foundation of 

 our science ; I should be more disposed to confer that title 

 upon physics and chemistry. Hov^ever, all such doubts 

 apart, the fact of being either a foundation or a backbone most 

 emphatically does not call for the size-privileges at present 

 accorded to morphology. We do not live in the foundations 

 of our houses, nor are they larger than the superstructure. 

 And as for backbones, it should not need more than a very 

 elementary acquaintance wjth natural history to realise that 

 an animal whose backbone weighed more than its muscles, 

 nervous system and viscera combined, would be biologically 

 very inefficient. 



As to the claim that other subjects can only be tackled 

 after a morphological survey of the animal kingdom, this must 

 be taken cum grano. It is in one sense obviously true, but in 

 another completely false. It is false if the knowledge of 

 morphology assumed is that detailed and intensive knowledge 

 which is usually required for a zoological degree. It is true 

 if we mean that a general survey of the main types of structure 

 and development found among animals is a desirable pre- 

 requisite to many other branches of biology. But such a 

 survey can be given in a small fraction of the time now allotted 

 to the morphological discipline ; what is more, if thus given, 

 the wood will not be obscured by the trees, which is unfortu- 

 nately too often the case {experto crede !) when the intensive 

 and detailed system is practised. There are only about twelve 

 phyla in the animal kingdom ; while the total number of groups, 

 whether sub-phylum, class, sub-class or order, of which the 

 budding zoologist need know the bare existence before he 

 embarks on general biology, is certainly less than a hundred, 

 and the characteristics of at least half of these he need only be 

 acquainted with in the most superficial way, provided that he is 

 well instructed in the ground- work of the phyla and sub-phyla. 



Another claim which I have often heard made is that the 



