Colour variation from plant to plant nevertheless occurs, 
much of it fairly minor changes in intensity or hue. Differen¬ 
ces in the concentration of a pigment make a colour more or less 
intense; for example, plants of the Large Purple Fringed-orchid 
C Platanthera grandiflora) (Reddoch and Reddoch 1987) have flow¬ 
ers that range from very pale to very deep lilac. Petrie (1981) 
illustrates his account of that species with photographs of a 
Gatineau Park plant (Reddoch 1976) with very pale flowers. 
If there are two or more pigments, changes in concentration 
of one of them may result in the hue varying from, for example, 
brown to gold, brown to red, or red to orange. Helleborine 
(Epipactis helleborine) has a great range of colours because its 
petals and sepals usually contain both a pink and a green pig¬ 
ment which can be quite variable in their relative concentra¬ 
tions. Such variations are not of great interest, however, and 
we will pass on to somewhat more dramatic differences. 
Variation in Pattern 
A more specific type of variation involves pattern changes. 
Many species have a fairly consistent pattern, aside from random 
little details like small dots. Thus, the Showy Orchid ( Gale- 
aris spectabilis) ordinarily has mauve sepals and lateral petals 
and a white lip. However, rarely one or more plants in a colony 
have lips that are not white but mauve like the rest of the 
flower. Although this form was given a name, forma willeyi, 
only in 1970, there are two Ottawa District collections more 
than a century old in the Agriculture Canada herbarium (DAO), as 
well as four more recently observed colonies. Both of the old 
collections were made and annotated by James Fletcher, one in 
1878 from Beaver Meadow, Hull (Reddoch 1979), "whole flower, lip 
& hood light mauve", and the second in 1879 from Patterson Creek 
Wood, Ottawa, "whole flower deep purple". More recently, there 
was a colony in Niven's Woods in Gloucester (Reddoch 1980) until 
that area was subdivided for houses. Figure 1 shows a plant 
from that colony. In 1973, we found a few plants of forma 
willeyi in a colony near the northwest corner of Kanata Pond. 
North of the Ottawa River, Hue Mackenzie photographed in colour 
a colony in the vicinity of the Larrimac Golf Course in 1966. 
There is also a colony in the lower part of Gatineau Park (Fig¬ 
ure 2), where we hope it is safe from development (and collect¬ 
ing). The forma willeyi is an addition to the checklist in 
Orchids of Ontario by Whiting and Catling (1986). 
A less spectacular but somewhat similar situation involved 
a plant of the Small Purple Fr inged-orchid (.Platanthera psy- 
codes) that we found along a roadside in Cumberland Township in 
1976 (Reddoch and Reddoch 1987). In this case, the sepals, 
while still lilac, were very much paler than the petals. This 
unnamed form had a striking two-tone appearance. Unfortunately, 
this plant and the normal ones in the colony have since disap¬ 
peared, presumably due to the township's herbicide spraying. 
72 
