"Organisms, especially animals, that are simultaneously individuals and colonies, pose dilemmas. They call into question all of our notions of individuality. The Huxley book, and its scientific and philosophical quandries are as current now, or even more so, than they were in 1912." 

Lynn Margulis

...The major portion of this book is devoted to showing that living matter always tends to group itself into these 'closed, independent systems with harmonious parts.' Though the closure is never complete, the independence never absolute, the harmony never perfect, yet systems and tendency alike have real existence. Such systems I personally believe can be identified with the Individuals treated by the philosopher, and I have tried to establish this belief. - Preface

Cloth 169 + xv pages, 5 1/4 x 8.
Reprint of fiirst edition published in 1912.