72 ON VARIETIES, lUCES, SUB-SPECIES, AND SPECIES. 



§ II. SPECIES OF LIVING BODIES CONSIDERED REI-ATIVELY 



TO THE GROUPING OF THE INDIVIDUALS RESPECTIVELY RE- 

 PRESENTING THEM, ARE THE OBJECTS OF FIVE GENERAL 

 DISTINCTIONS. 



As we have already said, a species comprehends all the in- 

 dividuals sprung from the same male and female : those in- 

 dividuals resemble them as much as possible relatively to the 

 individuals of another species ; they are characterised by the simi- 

 larity of a certain number of mutual relations existing between 

 the organs of the same name ; and the diflerences existing with- 

 out these mutual relations constitute varieties in general. 



Varieties are called simple, if these differences are not per- 

 petuated at all, or being perpetuated, are so only in small 

 numbers of places, and under circumstances that are not identical ; 

 they constitute races, if the differences taken as a whole are 

 decided, and capable of being perpetuated by reproduction pretty 

 constantly, and in certain places and circumstances not identical ; 

 tiiey constitute, lastly, sub-species, if tlie differences are well 

 defined, and can be constantly reproduced in any places, and 

 under any circumstances in which tiie individuals composing 

 them can live. 



These remarks show the necessity of paying attention to the 

 localities, or, to speak more generally, to all the external circum- 

 stances capable of modifying the living beings we may be study- 

 ing : in no other way can we give the precise value to the 

 modifications produced considered as characters of a species. 



We shall reconsider, but in a subordinate way, these definitions 

 in order to render them as exact as possible, noticing in the most 

 general view as regards the species, the subordination of the 

 different groups of individuals which constitute simple varieties, 

 races, and sub-species. 



In applying these new considerations to animal and vegetable 

 species taken as a whole, we are led to establish five sorts of dis- 

 tinctions, concerning the mutual relations which can exist be- 

 tween the several groups of individuals constituting simple 

 varieties, races, and sub-species, relatively to the notion of the 

 species to which these groups are allied. We shall distinguish 

 these distinctions by the first five letters of the Greek alphabet. 



Distinction Alpha. 



When the individuals composing a species resemble each other 

 too closely to allow of their being treated as varieties, and distin- 

 guished by separate names, any one of these individuals, or, if the 

 sexes are separate, any two of them may be regarded as the types 



