RRTTTSTT FORMS OF ORCHIS TWAUMTA 
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seen arc of this type: one from Cranham, Glos., had very large green 
bracts, tipped with dark purple, incurved, the highest topping the 
spike; another from Wotton, Norfolk, had very large, pale-green 
bracts and paler flowers. The colour-variations of O. incarncita are 
much greater than in the other allied species, and of considerable 
interest. Two, already referred to, are quite peculiar—namely, the 
pale straw-yellow and the rich maroon or mahogany-red. These may 
stand at opposite poles in the evolution of the species, the yellow 
being a retrograde mutation, and the maroon the most advanced. 
These both grow together at Kidwelly, along with a beautiful pink 
form, taller on the average than the maroon, and more slender than 
the yellow; it has a tinge of yellow in it, and there are several 
shades—to some extent the forms may cross. In respect of numbers, 
the straw-yellow is much the lowest. The tint we call “ maroon ” is 
very distinct and beautiful. We only know of it from South Wales, 
the Isle of Arran, and West Ireland. From the sands of Barry, in 
Scotland, the tints reported are purple, rose, pink, and white; evi¬ 
dently pure white may occur in some quantity, both of the taller and 
shorter tj^pes; pure dead-white we have found in very fine plants in 
East Anglia and the New Forest, and once, in a plant from Salop, 
growing in standing water, a semi-transparent white. The common 
orchis-purple is not infrequent, varying in shade from pale to a very 
deep almost blackish purple in a plant that came from County Clare. 
In West Wales, in Borth and Tregaron bogs, all the incarnate? s are 
purple, and the habit of the plant is somewhat distinct. The leaves tend 
to a yellowish tone, and are comparatively short and generally erect. 
Clarke’s figure of “ incarnata vera ,” referred to above, has flowers 
pale pink above, the lip darker, with yellow centre marked by red 
spots. Thus, apart from the white forms, we have four colour- 
groups—yellow, pink, purple, and maroon ; it would be useful to know 
the distribution of these groups and the extent to which they overlap. 
It is interesting to note that the bright yellow and maroon of the 
extreme colour-types corresponds to the very similar colour-variations 
of 0 . sambucina , which in other ways is very near to 0 . incarnata — 
indeed, in spite of the different habit of the tubers, O. sambucina 
may be a race of 0 . incarnata which has adapted itself to a drier 
habitat. We are inclined to think that O. incarnata is the basal 
species of the whole Marsh Orchis group. 
A number of hybrids are known ( Orchid Review, 1919, p. 169 ; 
Rep. Bot. Excli. Club, pp. 157 ff), though in our field-work we have 
never found more than occasional single specimens, in great contrast 
to the numbers in which hybrids of O. preetermissa and its var. 
pulchella often occur. We have noted hybrids of O. incarnata with 
O. preetermissa and its var. and with both types of 
O. maculata , i. e., O. Fuchsii and O. elodes (ericetorum ). It is not 
easy to describe most of these forms concisely, though when compared 
with the parents on the spot the relation is clear enough. In Journ. 
Bot. 1920, t. 556, are figured two variants of O. incarnata X latifolia 
(O. Ascii ersoni ana Hausskn.). Fig. 20 is from Salop, where it grew 
in a bog in a wood, and iig. 23 from the Kidwelly sands, where it 
