THE ORIGIN OF SPECIES. 35 



include the most polymorphous forms, it appears that 

 Babington's Flora gives them 251 species, Bentham's 

 only 112, a difference of 139 doubtful forms. These 

 are nearly the extreme views, but they are the views of 

 two most capable and most experienced judges, in re- 

 spect to one of the best-known floras of the world. The 

 fact is suggestive, that the best-known countries fm'- 

 .nish the greatest number of such doubtful cases. Illus- 

 trations of this kind may be multiplied to a great ex- 

 tent. They make it plain that, whether species in 

 l!Tature are aboriginal and definite or not, our practical 

 conclusions about them, as embodied in systematic 

 works, are not facts but judgments, and largely fal- 

 lible judgments. 



How much of the actual coincidence of authorities 

 is owing to imperfect or restricted observation, and 

 to one naturalist's adopting the conclusions of another 

 without independent observation, this is not the place 

 to consider. It is our impression that species of ani- 

 mals are more definitely marked than those of plants ; 

 this may arise from our somewhat extended acquaint- 

 ance with the latter, and our ignorance of the former. 

 But we are constrained by our experience to admit 

 the strong likelihood, in botany, that varieties on the 

 one hand, and what are called closely-related species 

 on the other, do not differ except in degree. When- 

 ever this wider difference separating the latter can be 

 spanned by intermediate forms, as it sometimes is, no 

 botanist long resists the inevitable conclusion. When- 

 ever, therefore, this wider difference can be shown to 

 be compatible with community of origin, and explained 

 through natural selection or in any other way, we are 



