be the nature of the individuality which absolutely and essen- 
tially separates one genus from the rest of the creation, must 
also exist in every other genus ; so that, if the species of any 
one genus are variations generated from one original type, 
the species of every genus must respectively have descended 
from a peculiar type; otherwise it would be apparent that 
the same thing is not meant when the words genus and 
species are used in the one case and in the other, and that 
the application of the words is vague and unscientific. If I 
have shewn that the species of one genus are convertible, and 
therefore of one origin, I have shewn that every genus must 
have had one original type, unless the genus which I bring in 
evidence shall appear to be in truth a division of an inferior 
grade, and not deserving of the name of a genus. Let us, 
therefore, inquire how the fact stands. It so happens, as if 
expressly to prevent the possibility of any doubt on that point, 
that the genus in which I have lately produced the proof of 
the most marvellous convertibility, is not only a valid genus, 
but embraces greater structural differences than any genus 
amongst the seven or eight thousand that have been defined— 
I mean the genus Narcissus, which, on account of those 
diversities, had been subdivided into a number of genera ; 
which supposed genera have been found capable of breeding 
together and re-crossing, so that not only intermediate forms 
can be originated, but one even of the supposed genera can be 
obtained in two or three generations from the capsule of 
another. This cannot stand as an isolated fact. It holds out 
a warning to all botanists, that on closer investigation it will 
be found, not merely that the genera of plants duly modified 
are the descendants of individuals which have branched into 
variations, but that a great portion of the seven or eight 
thousand are not even real individual types, but sections of a 
genus or kind embracing a certain class of variations, which 
have peculiar affinities to each other, and which in many, 
perhaps in most, cases cannot now intermix with plants of 
another section.” 
