INTRODUCTION 



TO THE 



STUDY OF BIOLOGY 



BY 



H. ALLEYNE NICHOLSON 



M.D., D.SC., M.A., PH.D.,'F.R.S.E., F.G.S. &c. 



PROFESSOR OF NATURAL HISTORY AND BOTANY IN UNIVERSITY COLLEGE, TORONTO : 



FORMERLY LECTURER ON NATURAL HISTORY IN THE MEDICAL SCHOOL 



OF EDINBURGH ', ETC. ETC. 



WILLIAM BLACKWOOD AND SONS 



EDINBURGH AND LONDON 



MDCCCLXXII 



Right of Translation is reserved 



