HYBRIDISATION AND CROSS-BREEDING, 61 
the observation of the breeder—especially the cross-breeder of plants or 
of animais. It is to him that we look for first-hand evidence as to the 
magnitude of variations. 
At this point a word of caution is needed. All those present are 
aware of the great and striking variations which occur in so many orders 
of plants when hybridisation is effected. As everyone knows, it is to 
those extraordinary “ breaks”’ that we owe perhaps the majority of our 
modern flowers. Such, for example, are Narcissus, Begonia, Pelargonium, 
Gladiolus, Streptocarpus, a great number of Orchids, Rhododendron, the 
Cineraria, and the like. JI mention the Cineraria, because I have 
personal knowledge of these hybrids, and because I notice that the view 
that our garden Cinerarias are not hybrids is being again repeated, in 
spite of the clear evidence, both of history and recent experiment, to the 
contrary. 
With such cases in view some may be disposed to say: “‘ Here are the 
great and striking variations we are seeking. These new forms are like 
new species—some would even take rank as new genera. May not the 
natural species have arisen in like manner by hybridisation?” The 
answer to this question, however, is almost certainly No. And herein I 
believe most, if not all, professed botanists and zoologists will agree. To 
go into the matter fully here is impossible ; but for many reasons, most 
of which have often been repeated, there is, I think, no good evidence for 
supposing that any natural species, whether of animal or plant, arose by 
direct hybridisation. Tempting as it may at one time have been to hope 
that we should thus get a short cut to the origin of species, few, I 
think, are now sanguine of such an issue. It is not in this direction that 
we can look for that advancement in knowledge which I believe will 
surely come from the work of the cross-breeder. 
I am far from saying that these striking hybrids are without scientific 
interest, or that they have no bearing on the problem of species. I wish 
only to say that it is pretty clear that they have not the direct bearing 
which they would have if it could be supposed that natural species arose 
as similar hybrids. 
The interest in the cross-breeder’s work lies, as I think, in a somewhat 
different field. Whatever view we adopt of the origin of species—pro- 
vided that we believe in the doctrine of Descent at all—we believe that 
every species has been actually produced from something like itself in 
general, though different in some particular. Wherever these two closely 
allied varieties exist, the problem of species is presented in a concrete 
form: How did variety A arise from variety B, or B from A, or both from 
something else? This question involves two further questions :— 
1. By what steps—by integral changes of what size—did the new 
form come into being ? 
2. How did the new form persist? How was it perpetuated when 
the varying individual or individuals mated with their fellows ? 
Why did it not regress to the form from which it sprang, or to 
an intermediate form ? 
To those who admit this reasoning it will be clear that the whole 
question of the origin of species turns on the relationship of each species 
