GENERA. 155 



II. Genus. 



This division, which is designated by a pecuhar title, 

 serves as a surname to the species which it includes. 



If we are to consider as a genus^ every division by which 

 species are distributed into groups, and regai'd it as only one 

 step higher in the scale of our classifications, the number 

 of species which it can include will in general be few in 

 number. Indeed, if we employ the twofold method of 

 division, by positive and negative characters, the lowest 

 groups will seldom contain more than two species. When 

 genera occur greatly exceeding in species this limited num- 

 ber, we may safely conclude, that the structure of the spe- 

 cies is imperfectly understood, and that the distinguishing 

 characters ai*e chiefly derived from the modifications of one 

 organ. 



1. Generic Name. — The term employed to "designate a 

 genus, is always a substantive in the singular number, and 

 nominative case. In order to avoid all grounds of confu- 

 sion, and that the term may lead the mind to no other 

 image, primitive words, and such as are appropriated to 

 other objects, are carefully avoided. For similar reasons, 

 all words indicative of comparison or resemblance, or those 

 ending in oides, are rejected. Neither hybridous nor bar- 

 barous terms are employed. Those in common use are al- 

 most exclusively derived either from the Greek or the La- 

 tin*. 



It is somewhat remarkable, that, in mineralogy and bo- 

 tany, generic titles should, in many cases, be derived from 

 the names of those naturalists who have contributed to the 



• The " Philosophia Botanica," 8vo, 1751,-6. of Linn5;us, may be per- 

 used with advantage, on the subject of Nomenclature. Many of his rulcf , 

 however, arc empyrical, and have never been attended to by naturalists. 



