H- n 



AN INTRODUCTION 



CLASSIFICATION OF ANIMALS 



BY 



THOMAS HENRY HUXLEY, LL.D., F.R.S., 



PROFESSOR OF NATURAL HISTORY IN THE ROYAL SCHOOL OF MINES, AND PROFESSOR OF COMPARATIVE 

 ANATOMY AND PHYSIOLOGY TO THE ROYAL COLLEGE OF SURGEONS OF ENGLAND. 



LONDON: 

 JOHN CHITECHILL & SONS, NEW BUKLINGTON STREET. 



MDCCCLXIX. 



