Vlll PREFACE. 



author, which he would strongly recommend to such of 

 his readers as can gain access to it. He would remark, 

 in conclusion, that any systematic Treatise like the present 

 must consist, in great part, of materials collected by other 

 naturalists ; and that the merit of an elementary work 

 must consist rather in the judgment shown in the selec- 

 tion and arrangement of the materials, than in the origi- 

 nality of its contents. How far he has succeeded in his 

 present attempt, it will be for his readers to decide. 



