Figures 1 and 2. The coloured-lipped form of the Showy Orchid 
from Niven's Woods (left) and Gatineau Park (right). Note that 
the lips are the same shade as the hoods. 
Absence of Anthocyanins 
The next group of variants results from the complete fail¬ 
ure of the plant to produce the red, pink or purple anthocyanin 
pigment. This is an uncommon, but widespread and quite drama¬ 
tic, occurrence among flowers. Perhaps the best known local 
example is the rare yellowish-white form of the Red Trillium. 
Gerardia and Gaywings provide other examples. This type of 
colour change seems to be of little interest to most botanists, 
but intrigues field naturalists and even provides a living for 
some horticulturalists. An example is the white Poinsettia, 
although here the red pigment was in the bracts rather than the 
flowers. Among the native orchids of Canada, almost every 
species with noticeable amounts of red pigment is known to have 
a named form lacking that pigment. Several of these occur in 
the Ottawa District. 
The term "albino" is often used to describe an individual 
in which a pigment, normally present, is missing. If no other 
pigments are present, the result will be white, as the word 
implies. However, it is important to note that such an absence 
does not always yield white. When a species ordinarily has two 
or more pigments, only one is likely to be absent. Then the 
colour will not be white but will depend on the colours of the 
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