68 The Different Modes of Origin of new Species. 
is evidently clue, in the vast majority of cases, to retro- 
gressive development or latency, as I have already at- 
tempted to show. 
There is a close analogy between the formation of 
these varieties and that of certain species. The origin 
of varieties (such as Var. hirsutissinia, spinosissima and 
ciliata) as the result of the intensification of characters 
is a much rarer phenomenon. This form of variety, 
which seems to be of very little importance in the evolu- 
tion of the vegetable kingdom, may be called subprogres- 
sive, and the phenomenon of its origin subprogressive 
formation of species. 
The parallel, retrogressive, and subprogressive modes 
of origin have this in common that they only provide new 
combinations and do not contribute new units or any es- 
sentially new elements to the progressive evolution of the 
vegetable kingdom. In this respect they stand in sharp 
contrast to progressive formation of species. 
There is another series of phenomena to be mentioned 
here, of still less significance in the phylogeny of plants. 
The first of these is the manifestation of old, latent char- 
acters. A whole series of anomalies are so widely dis- 
tributed in the vegetable kingdom, or at least among 
flowering plants, that it is almost impossible not to as- 
sume a common cause for them. This cause must be 
a latent character that has arisen in some common ances- 
tor and therefore must be of great antiquity. The com- 
monest and best known example of a widely distributed 
anomaly of this kind is that of fasciation, instances of 
which in almost any desirable number of species can be 
collected in the course of a few years. It appears that 
almost every species amongst Coni ferae and Monocotyl- 
edons, but especially among Dicotyledons, can exhibit 
