6 THE ORCHID REVIEW. [JANuARY, 1907. 
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T page 270 of the Orchid Review for November last it is recorded that 
Cattleya Mantinii x C. Hardyana, has produced the white sepelled 
and petalled C. Corona alba, and it is remarked that if the C. Hardyana 
used was not the albino form, then C. Corona alba would show how white 
forms may sometimes arise. In November, 1912, I stated: ‘‘ My 
experience teaches me that whites can be built up from purple on the one 
side and yellow on the other,” and I gave a number of examples. This 
experience has found echo in many other collections, and they have been 
recorded. Arising out of this case you open up (p. 257) a very interesting 
discussion upon Mendelism and its relation (or want of it) to hybrid Orchids, 
and more particularly the question as to why C. Dowiana aurea does not 
transmit the yellow of its sepals and petals to its immediate offspring. 
Before dealing with the two points raised I should like to say that I have 
not found the study of the Mendelian theory of the slightest use when 
applied to Orchids. It may lead to a very interesting analysis, but such 
analysis is useful only in so far as the result provides material for building 
up something. It must be remembered that Mendelian analysis is 
quantitative as well as qualitative, and the analysis of sweet peas is a simple 
matter when compared with the analysis of complicated hybrid Orchids, of 
the first, second, and third generations. The aims of the hybridist are very 
high, for not only does he want flowers of a pre-determined colour; but he 
also wants healthy, vigorous, floriferous plants, with large flowers, of good 
shape and substance. The complications are enormous. One can scarcely 
conceive that it was originally intended that the Mendelian theory should 
cover all these complicated requirements, or be expected to analyse them 
quantitatively as well as qualitatively. 
What, then, is there to guide the Hybridist in his effort to obtain a 
desired colour? The study is a fascinating one, but at the same time very 
difficult. Only very broad lines can be laid down, and these may not be 
absolutely reliable, for the range of one’s personal experience is apt to be 
limited, and if one goes outside this, it is an unfortunate fact that records 
as to colour are not always reliable. 
One ought not to be surprised that C. Mantinii x Hardyana has 
produced a flower with white sepals and petals; in fact, in the light of all 
the previous records, it would have been surprising if it had not done so. 
But that anyone should be able to say what the exact proportion of whites 
there will be to coloured is outside the range of practical experience. 
Many Hypbridists can, from their experience, tell what the “chances” are 
Reces| ALBINISM AND COLOUR IN ORCHIDS. 
