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DIRECTIONS FOR STUDENTS. 



This text-book embraces not only a system of 

 to be used for ascertaining the names of animals : 

 but also the most important elementary principles 

 of the science of Zoology, given in a concise fami- 

 liar manner. 



The student should commence at page 7 and 

 study the whole attentively to the middle of page 

 41. Then read the remarks on pages 53, 62, 76, 

 79, 91,94, 96, 98, ill, 118, 120, 123, 125 and 

 129. Also the directions on pages 133, 134 and 

 135. Also the sections and remarks upon the spe- 

 cies, under the generic names Silpha, p. 253, and 

 Vespa, p. 275. 



Several species of American fresh- water shells 

 are described for the purpose of exercising students 

 in the study of shells; chiefly from Say and Barnes ,> 

 most of which they propose as new. More might 

 have been copied from Say, in Long's Expedition, 

 But I think that most of these new species require 

 reviewing. On comparing the characters with, 

 descriptions of European species, I should be in- 

 clined to recommend an exchange of specimens 

 with European naturalists, before they are offered 

 as new, and in some cases a comparison of the 

 proposed new species with each other, especially 

 some of the new species of Mya, of the section 



