EDITOR'S INTRODUCTION xix 



his friend Charles Sumner. Subscribers were promised books that 

 would illuminate "the wonderful diversity of the animal creation 

 of this continent" by describing all classes of animals, such natural 

 history to be illustrated by accurate and expensive drawings. The 

 first monograph would portray the embryology, geographical distri- 

 bution, and classification of North American turtles. Most important, 

 these special studies would be preceded by an "Essay on Classifica- 

 tion" that would supply "a new foundation for a better appreciation 

 of the true affinities, and a more natural classification, of animals." 

 This venture in taxonomy, Agassiz promised, would enable natu- 

 ralists to determine "with considerable precision, the relative rank 

 of all the orders of every class of animals" and would furnish "a 

 more reliable standard of comparison between the extinct types of 

 past geological ages and the animals now living upon the earth." ^ 



When the first two volumes comprising the Essay and the analysis 

 of turtles were published in the fall of 1857, Agassiz was very proud. 

 He was acutely aware of their importance. His words to a colleague 

 when just beginning the project were revealing: "I have tried to 

 make the most of the opportunities this continent has afforded me. 

 Now I shall be on trial for the manner in which I have availed 

 myself of them." " But it is doubtful whether the admiring public 

 learned very much from the intricate and highly specialized descrip- 

 tions of North American Testudinata. They could not fail to be in- 

 structed by the Essay on Classification. 



Agassiz asserted in his preface that the Essay would be of interest 

 and value to all. It would serve as a "text-book of reference for the 

 student, in which he may find notices of all that has been accom- 

 plished in the various departments of Natural History." Moreover, 

 he boasted that his audience was so wide that "I expect to see my 

 book read by operatives, by fishermen, by farmers, quite as exten- 

 sively as by the students in our colleges or by the learned profes- 

 sions." The Essay would call attention to "the mode of life of all our 

 animals, to their geographical distribution, their natural affinities, 

 their internal structure, their embryonic growth, and to the study 



^Ibid., pp. 3-4. 



"Agassiz to Samuel S. Haldeman, May 31, 1855, Samuel S. Haldeman Papers, Academy 

 of Natural Sciences of Philadelphia. 



