5° THE ORCHID REVIEW. (FEBRUARY, 1913+ 
ORCHID BREEDING. 
As a hybridist who has worked on the principle of crossing plants with a 
view to their improvement, it is rather disconcerting to be told that we have 
been working on the wrong lines. We have not taken into consideration a 
mysterious something called the ‘principles of genetics.’ We could 
distinguish characters that we wished to perpetuate, to combine, or to 
modify, but we failed to ascertain beforehand whether they were heritable 
or not. The result is a crowd of failures, and it is even suggested that the 
only safe method to adopt is to make a fresh start. A plant may be 
homozygous for one character, heterozygous for another, and zerozygous 
for a third character, and so on, but each individual plant has a definite 
germinal, or gametic constitution, which can be ascertained by cross- 
breeding it with other plants. In this way a factorial analysis of the plant 
can be made. All future breeding from that plant is reduced to practically 
a certainty. But how about the heritable characters of the other plant 
with which it is crossed? A little earlier we had been told that it all 
depended on whether the plant had a double dose of the desired character 
or not. How am I to set about finding these heritable characters and 
separating them from the undesirable characters that may also be heritable? 
—Hypripist. 
(In our opinion the whole argument is based upon a fallacy. Species are 
homozygous, 1 all their characters, until crossed—that is to say they come 
true from seed. They have a double dose ofall the characters, if the fact 
must be stated in these terms. The trouble does not arise with the plant, 
but with the hybridist, who mixes the characters, thus producing hybrids, 
whose characters are necessarily heterozygous. The remark about a double 
dose of a given character simply means that the said character is present 
in both the parents, and like produces like. A plant that is homozygous 
when crossed with another that possesses a similar character will be 
heterozygous when crossed with one possessing a different character, but a 
single character does not make a plant, and hybridists invariably work for 
several characters at the same time. Suppose a yellow Cattleya is the 
desideratum. That colour must be combined with, let us say, size, shape, 
and constitution, if the hybrid is to be what has been termed a “ winner.” 
“‘Genetics” is simply a convenient term for everything that concerns the 
science of heredity, and hybridists have been studying it from the time that 
the intermediate character of the first hybrid was observed. What 
hybridists have to do is to keep their eyes open and conduct their 
experiments according to their experiences and those of their fellow-workers. 
They must continue to “‘ use the best individuals of the best varieties of the 
best. species of the best genera ’—yes, andthe best hybrids, too, even if 
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