ne, 
66 JOURNAL OF THE .ROYAL HORTICULTURAL SOCIETY. 
properties and their powers of entering into genetic combinations, just as 
the chemist investigates the powers of his bodies to enter into, chemical 
combinations. : .s 
To lump all the different manifestations of variation together as 
varieties,’’ and to rest there, is to give up in despair. 
Similarly, it is certain that what we call “species’’ is a mixture of 
different phenomena, or rather of different classes of phenomena con- 
founded under one name. I look to the study of cross-breeding to un- 
ravel that extraordinary mass of confusion. I look to this method of 
investigation to deliver us from the eternal debates on the subject of 
what is specific rank and what is not. 
On the one hand we have at the present day many who devote them- 
selves entirely to discussions of this nature, though they know in their 
hearts that their views correspond to no natural fact whatever. On the 
other hand, many in disgust and impatience reject the whole thing. 
“There is no such thing as species,” say they. Both sides are surely 
wrong: there is such a thing as species, and we have to find out what 
are the properties of species. 
It is true that, as to most species and varieties, artificial breeding is 
impossible, but in numerous cases a beginning can be made. Take 
merely the phenomenon of local varieties, or local species, or local races, 
about which such weary discussions have arisen. Each of these offers a 
particular example of the Evolution problem. In numbers of such cases 
an investigation of the behaviour on crossing could be practised, and a 
very few such experiments would, I venture to predict, do more to 
establish true views of the relation of species and varieties than the 
labours of systematists will do in ages. 
To come much nearer home, we do net know for certain the true 
relationships—in this special sense—between the varieties of the com- 
monest domestic animals and plants. For example, I have been trying 
to investigate these relationships between the several kinds of comb in 
domestic poultry. Ihave thus far found no one who can tell me for 
certain what happens when they are crossed. The various forms of comb 
in our breeds of poultry—simple comb, pea-comb, rose-comb, &¢.—are 
important structural features, which differ from each other very much as 
many natural species do. ‘The answer generally given is that the result 
of such crossing is uncertain—that sometimes one result occurs, and 
sometimes another. This, of course, merely means that the problem 
must be studied on a scale sufficiently large to give a statistical result. 
There is here an almost untouched ground on which the properties of 
specific characters can be investigated. Many similar examples might be 
given. 
True and precise experiments in these fields so ready to our hand 
have never been made, We appeal to those who have the opportunity to 
use it for the advancement of this fascinating line of research. It is 
delightful to form great collections of animals or plants, and to ‘ bring 
out a novelty’’ may be an exhilarating sensation; but if anyone will 
abandon these well-worn pursuits, and devote himself to experimental 
cross-breeding, he will soon haye his reward, for no line of research is 
likely to prove more fruitful. 
