iv PREFACE. 



initials, and both are enclosed in brackets, so that the reader 

 may readily distinguish between MM. Agassiz and Gould's 

 text, and the additions made thereto. 



The number and excellence of the wood-cuts form an im- 

 portant feature in this edition. With the exception of those 

 belonging to the chapters on Embryology, and the Meta- 

 morphoses of Animals, they are nearly all additional, by which 

 the original number is more than doubled : the American 

 edition having only 1/0 wood-cuts, whilst the present con- 

 tains 390. The beautiful drawings illustrative of human 

 Osteology were engraved by Branston for the valuable Manual 

 on the Bones by John F. South, Esq. ; those illustrating the 

 chapters on Circulation, Respiration, Secretion, and the De- 

 velopment of the Chick, are chiefly from Wagner's " Icones 

 Physiologic^" and were engraved for the English translation 

 of that author's Elements of Physiology ; the other figures 

 are selected from various sources, references to which are 

 given in the Table of illustrations. 



It has been the study of the Authors and of the Editor to 

 exclude as much as possible a technical phraseology from 

 the following pages ; but as the use of scientific terms could 

 not altogether be dispensed with, the Editor has given an 

 interpretation of them in a copious Glossarial Index. 



T. W. 



,/iam, October, 1851. 



