Horticultural and Systematic Varieties. 57 
place the progressive origin of species, that formation of 
new characters to which in the main the evolution of the 
plant kingdom is due. On the other hand there is a 
whole series of other types which are now, so far as it 
is possible to judge, mainly confined to the lateral branches 
of the phyletic tree. With regard to these however we 
must content ourselves at present with indirect methods 
of investigation. 
DARWIN'S statement that varieties are incipient spe- 
cies is well known. So also are the words of one of the 
most famous authorities 1 on horticulture, VERLOT : Toute 
varicte a d'abord existe a I'ctat de variation. These two 
generalizations are evidently based on phenomena en- 
tirely different from those with which we have become 
familiar in Ocnothera. They constitute, so to speak, 
the other extreme of the series. 
I propose therefore now to investigate the manner in 
which "variations" in the sense of so-called structural 
abnormalities or anomalies (and not the individuals which 
exhibit variation in accordance with QUETELET'S law) 
arise, and how they result in the origin of "species." 
But here we come across an obstacle on the very threshold 
of the inquiry in the manifold meanings of the word 
variety. 2 It will soon become clear that horticultural 
and systematic varieties are to be considered as categories 
of entirely different values. But both DARWIN'S and 
VERLOT'S sentences just quoted are based on data ob- 
tained from horticultural varieties ; and we must now 
1 B. VERLOT, Production ct fixation dcs varictcs, 1865, p. 100. 
5 The general conception of this term is that formulated by CAR- 
RIERE in the following words: "On nomine varictc tout individu qui, 
par quclque caractcrc quc ce soit, se distingue d'un on de plusicurs 
autres avec Icsqucls on le compare ct quon considere comme apparte- 
nant a un meme type specifique (Production et fixation dcs varietes, 
1865, p. 6). 
