Preface 



The chordates are a vast assemblage of animals so diversified as to 

 include sea-squirts, sharks, toads, snakes, larks, bats, whales, mice, and 

 men. Any one animal confronts us with many aspects — structural, 

 functional, ecologic, geographic, geologic, historic (individual life- 

 history, racial history), behavioristic, psychic, philosophic. Chordates 

 differ as to the nature and degree of diversity of their activities. To 

 hop, sit, eat, and reproduce epitomizes the life of a toad. To these 

 elemental items of living, the human chordate adds many and much — 

 clothing, cities, skyscrapers, motor mechanisms, telecommunication, 

 medication. He writes poetry, composes symphonies, wages world wars, 

 splits atoms, and fills thousands of libraries with millions of books deal- 

 ing with everything, but mostly with himself. An adequate treatise on 

 the chordates must include all of this. It is at once evident that, as a 

 title, "The Chordates" has an inclusiveness ridiculously out of propor- 

 tion to the size of this book. The attempt to devise a title which should 

 fairly indicate the scope of the book resulted in a plethora of words 

 which would have overtaxed a title page and probably would have 

 condemned the book as one containing a little of everything and not 

 much of anything. 



Writing a book is inexcusable unless the product can claim some de- 

 sirable feature not possessed by other books. What does this book try to 

 do? 



For an unmentionable number of years the author conducted a col- 

 lege course in comparative anatomy of backboned animals. It was done 

 in the conventional way — lectures, laboratory work, and collateral 

 reading. During the earlier years all the formal work was done in one 

 room which combined lecture room, laboratory, and library. An ample 

 case contained books whose titles covered in a broad way the biologic 

 field of the course. The books were at all times freely accessible to the 

 students. 



