HYBRIDISATION AND CROSS-BREEDING. 59 
HYBRIDISATION AND CROSS-BREEDING AS A METHOD 
OF SCIENTIFIC INVESTIGATION. 
By W. Bateson, M.A., F.R.S., 
University of Cambridge. 
Ir was with a special pleasure that I accepted the kind invitation of the 
Council to address this Conference of persons interested in hybridisa- 
tion. Of all the methods which are open to us for investigating the facts 
of Natural History there is perhaps none which is more likely to bring 
forth results of first-rate importance. Not only is the field a vast one, 
but the work is ready to hand. Though the patience and labour needed 
are very great, the practical methods are simple, and can be in many 
cases carried out by any person who has leisure and is able to carry out 
anything accurately. Leisure, accuracy, and a garden of moderate 
extent are almost the only equipment necessary for such work. On the 
other hand, the scientific importance of the results to be obtained is 
transcendent. ; 
It is perhaps simpler to follow the beaten track of classification or of 
comparative anatomy, or to make for the hundredth time collections of 
the plants and animals belonging to certain orders, or to compete in the 
production or cultivation of familiar forms of animals or plants. But all 
these pursuits demand great skill and unflagging attention. Any one of 
them may well take a man’s whole life. If the work which is now 
being put into these occupations were devoted to the careful carrying 
out and recording of experiments of the kind we are contemplating, the 
result, it is not, 1 think, too much to say, would in some five-and- 
twenty years make a revolution in our ideas of species, inheritance, 
variation, and the other phenomena which go to make up the science 
of Natural History. We should, I believe, see a new Natural History 
created. 
It seemed to me that I could not better make use of this opportunity 
than by indicating, as far as I can, some of the aims which I think a 
worker in this field should put before him, and the class of work which, 
as it seems to me, is most likely to prove fruitful in bringing about 
the result I have indicated. 
The problem, it is assumed, on which all such work is to be brought 
to bear is the problem of species. 
I must ask you for a moment to consider the present position of 
knowledge in regard to Evolution and the nature of Species—for it is 
with a clear reference to the problem of species that breeding experi- 
ments, in the first instance, should, in my opinion, be undertaken. We 
see all living nature—animals and plants—divided into the groups 
which we call species, groups often so sharply marked off that there 
can be no doubt where they begin and end; groups often, on the other 
hand, so irregularly characterised that no two people would divide 
them alike. What are the causes that brought this about and keep it so? 
What are the facts underlying this phenomenon of species? For pheno- 
menon it is; and, believe as we may that all these forms are related in 
