FEBRUARY, 1918.] THE ORCHID REVIEW. 31 
remarked I have always found fungi in the young seedlings which 
cultivators have sent me, as well as in the young seedlings of Orchids 
collected in their native homes. 
And his photograph provides conclusive evidence on this point. One 
tube shown contains seeds of an Odontoglossum that had been sown 
aseptically on the surface of a mass of nutrient jelly. The seeds had been 
sown for a period of four months. They turned green and swelled slightly, 
but made no further progress; a perfectly familiar experience. The second 
tube contained seeds of the same plant, and had been treated in precisely 
the same way, except that the jelly had been inoculated for two and a half 
months with a fungus found on the roots of the Odontoglossum. This 
fungus had developed, forming a delicate network on the surface of the 
jelly, and this in turn had affected the seeds, which are shown developing in 
a regular manner. 
It was necessary to use a fungus obtained from an Odontoglossum, for 
those obtained from Cattleya and Cypripedium produced no effect. Even 
that obtained from different Odontoglossums was variable, some bringing 
about germination more quickly than others, while some, though identical 
in appearance, had no appreciable effect. The cause of this variation is not 
apparent, unless more than a single species of fungus is concerned. Burgeff, 
indeed, seems to suggest that each species of Orchid has its own special 
fungus, but this we regard as highly improbable and against the weight of 
evidence. The subject, however, is still veiled in obscurity, and further 
experiments are necessary on this point. R.A.R 
The germination of Orchid seeds upon a fungus substratum, as demon- 
strated by Dr. Burgeff, was highly successful, seedlings of several different 
genera being raised in this way. The process was to prepare a gelatinous 
substance, of which Agar-agar was the base, and sterilize it by heat. A 
portion of the jelly was then placed in bottles of a similar type to those used 
for milk in the London district ; the jelly was then innoculated with a pure 
culture of a fungus obtained from the root of the kind of Orchid which was 
being worked with, and the seeds were afterwards introduced. The bottles 
were then closed with a piece of parchment, and placed in a suitable 
temperature. These operations were conducted by Dr. Burgeff himself, 
and, as he says, the pure culture of the root fungus penetrates into the 
germ of the seed (which is devoid of endosperm), and provokes germination, 
thus supplying the young seedlings with the necessary nourishment. 
Under these conditions germination proceeds regularly, and the seedlings 
remained in the bottles until they became fit for a different compost. The 
bottles were then broken and the plants removed. The greatest difficulty 
experienced by Dr. Burgeff was to find a gardener who was able to continue 
