GENERA. 159 



them by the name of the oldest established genera, and 

 bestowing upon them a patronymic termination, as des or 

 dee. The latter is generally preferred as a termination, 

 since it never occurs in generic names ; while the former, 

 being of frequent occurrence, may, if employed, occasion 

 mistakes. 



In all these different divisions, it is of importance to ex- 

 press briefly, the essential distinguishing marks, in order to 

 facilitate research ; and to enumerate all the common pro- 

 perties, to avoid the necessity of repetition. 



The observations which have now been offered, lead to 

 the conclusion, that Species alone, in the divisions of 

 zoology, are permanent, all the others being subject to 

 change. The higher divisions are of our own creation, and 

 are altered occasionally, to make them correspond with our 

 increasing knowledge. The discovery of a few new spe- 

 cies, compels us to form sections in a genus, or, instead of 

 these, to construct new genera. The old genus, then, be- 

 comes a family, and a similar advancement of rank takes 

 place in all the higher divisions. Many of the Linnaean 

 genera are now at the head of eight or ten inferior divi- 

 sions, and the genera of modern systems, in consequence of 

 future discovery, will, in their turn, experience a similar 

 elevation. 



