PREFACE. 



Four years ago I published the grand divis- 

 ions, the classes and orders of Cuvier's Le Kegne 

 animal distribue d' apres son organization. No- 

 tice was given at the time, that it was my inten- 

 tion to publish a translation of Cuvier's genera. 

 But soon afterwards I was assured that two or 

 three of our best Zoologists contemplated the ex- 

 ecution of an elementary system of Zoology. My 

 pupils have now waited for the promised work 

 about two years, since my edition of the classifica- 

 tion of Cuvier has been exhausted. I was at 

 last driven to this undertaking ; which I entered 

 upon with extreme reluctance. Not on account 

 of love of ease, or that modest diffidence usually 

 complained of by authors. But because it may 

 retard the publication of the promised system of 

 American Zoology, which, it is confidently hoped^ 

 some competent naturalist will ere long complete. 



In answer to this objection it has been observ- 

 ed by my friends, that such a small book, present- 

 ing a familiar outline of the science, might serve 

 as a pioneer for a full system ; as my Manual of 

 Botany did for the enlarged works of Elliott and 

 Torrey. More than four thousand copies of the 

 Manual, in the hands of botanists, awakened a 



