A CENTURY OF ZOOLOGY IN AMERICA 403 



from, but also, and perhaps in even greater degree, in the 

 popularization of science. In the latter direction were 

 his inspiring lectures before popular audiences and the 

 early publication of a zoological text-book. This book, 

 published in 1848, was entitled "Principles of Zoology, 

 touching the Structure, Development, Distribution and 

 Natural arrangement of the races of Animals, living and 

 extinct, with numerous illustrations." It was written 

 with the cooperation of Augustus A. Gould. The review 

 of this book in the Journal (6, 151, 1848) indicates clearly 

 the broad modern principles underlying the new era 

 which was beginning for American zoology. 



"A work emanating from so high a source as the Principles 

 of Zoology, hardly requires commendation to give it currency. 

 The public have become acquainted with the eminent abilities 

 of Prof. Agassiz through his lectures, and are aware of his 

 vast learning, wide reach of mind, and popular mode of illus- 

 trating scientific subjects . . . The volume is prepared for 

 the student in zoological science; it is simple and elementary 

 in style, full in its illustrations, comprehensive in its range, yet 

 well considered and brought into the narrow compass requisite 

 for the purpose intended." 



The titles of its chapters will show how little it differs 

 in general subject matter from the most recent text-book 

 in biology. Chapter I, The Sphere and fundamental 

 principles of Zoology; II, General Properties of Organ- 

 ized Bodies ; III, Organs and Functions of Animal Life ; 

 IV, Of Intelligence and Instinct; V, Of Motion (appa- 

 ratus and modes) ; VI, Of Nutrition; VII, Of the Blood 

 and Circulation ; VIII, Of Respiration ; IX, Of the Secre- 

 tions ; X, Embryology (Egg and its Development) ; 

 XI, Peculiar Modes of Reproduction; XII, Meta- 

 morphoses of Animals ; XIII, Geographical Distribution 

 of Animals ; XIV, Geological Succession of Animals, or 

 their Distribution in Time. 



A moment's consideration of the fact that all these 

 topics are excellently treated will show how great had 

 been the progress of zoology in the first half of the nine- 

 teenth century. The sixty years that have elapsed since 

 the publication of this book have served principally to 

 develop these separate lines of biology into special fields 

 of science without reorganization of the essential princi- 



