THE ORCHID REVIEW. 
[August, 
under Dendrobise. Much more recently flowering specimens of Acoridium! 
were discovered, and though they were relegated to their true order, their 
identity with Nees and Meyen’s imperfect specimen was not at first 
recognized. Ultimately, however, this was established by Rolfe, who also- 
showed that Acoridium was identical with Bentham’s genus Platyclinis, 
But inasmuch as the former name had precedence over the latter by 
more than 40 years, Platyclinis became reduced to a synonym of 
Acoridium; - About 1907 J. J. Smith reconstructed the genus Dendro- 
chilum so as to include within it all Orchids hitherto placed under 
Acoridium and Platyclinis. These two genera are now reduced to the 
rank of subgenera or sections. This arrangement appears to have 
received the approval of botanists generally, and has been adopted 
by Ames, and also by Pfitzer and Kranzlin in their monograph of the 
Ccelogyneae (Das Pflanzenreich). 
COLOUR OF CCELOGYNE PANDURATA. 
HE most remarkable thing about the genus Coelogyne, states Mr. T. D. 
^ A. Cockerell ( Torreya , vol. xix., Nov., 1919), is that the bp in some of 
the species is marked with black. I have before me a number of fresh flowers 
of C. pandurata. The profuse marking of the pale greenish lip is dull black,, 
with a very faint rusty tint, 'fhe small concavity at the extreme base is 
cinnamon-brown. The other segments are pale yellowish green* The 
column is suffused with apple-green, especially at the tip. 
On examining the black markings of C. pandurata under the microscope 
and in sections, Mr. Cockerell found that they were entirely superficial,, 
situated on innumerable closely-placed small papillae. By transmitted light 
they appear brown, and the cinnamon colour of the basal depression is 
doubtless due to the sanie pigment in dilute form. The pigment gives none 
of the anthocyanin reactions, nor does it look like anthocyanin. It is 
soluble in strong alkaline solutions, and produces a cherry-coloured liquid,; 
This readily stains paper, but does not change colour on drying. Acid 
almost entirely discharges the brown colour. 
Mr. Cockerell further states that he is indebted to Dr. F. Ramaley for 
the suggestion that the reactions resemble those of turmeric, derived from 
Curcuma (Zingberaceae). The pigment in turmeric is curcumin, C H H ie O,. 
It seems evident that Coelogyne possesses a closely related though doubtless 
distinct pigment. Even in species such as C. speciosa and C. asperata, in 
which the lip is marked with red or cinnamon, there is probably no 
anthocyanin at all. Pfitzer and Kranzlin remark that blue or blue-violet 
colours are lacking in the whole tribe Coelogyninae, but the genus Pleiorie, 
to judge from the descriptions, must certainly possess anthocyanin. 
