JANUARY, 1909.] THE ORCHID REVIEW. 13 
day, and overhead as well, and the plants will soon get established again, 
especially if the temperature can be raised 5° to 10° to help them to start 
again. 
TEMPERATURES should be kept as even as possible during this month. 
If the blinds are run down at night it will be found a great help, especially 
where a boiler is not over large. 
The temperatures should run about as follows :— 
Cool house, night 50°, day 55°. 
Intermediate house, night 55°, day 60°. 
Cattleya house, night 60°, day 65°. 
Stove or East Indian house, night 65°, day 70°. 
Houses should be damped so as to preventa fiery smell being noticed 
when entering them, always remembering one is growing Orchids, not Cacti. 
Orchids will not thrive in a dry atmosphere. 
EPIDENDRUM x KEWENSE: A MENDELIAN EXPERIMENT. 
WHEN the interesting Epidendrum x kewense was described six years ago 
(O.R. xi. p. 6) it was remarked : ‘A few flowers have been self-fertilised, 
and ifthe hybrid proves fertile the results should be specially interesting, for 
Mendel’s theory assumes that the gemmules of hybrids remain pure, and 
therefore self-fertilised seedlings ought to revert in certain characters.’ The 
fertilised flowers came to nothing, and I therefore fertilised the hybrid with 
both its parents (all being in flower together), and also reversed the crosses, 
with results that have already been described (O.R. xv. p. 58). Over a year 
later, when the plants were stronger, another attempt was made to self- 
fertilise the flowers, and this time a good capsule and abundance of seeds 
were obtained (O.R. xiv. p. 272 ; xv. p. 58). And now one of the seedlings, 
raised at Burford, has expanded its first flowers, and with others, some of 
which are showing spikes, has been sent to Kew. The first result is that 
E. X kewense has reproduced itself true from seed, for parent and offspring 
resemble each other almost as closely as in the case of seedlings of a pure 
species. Whether the other seedlings will behave in the same way remains 
to be proved, so that further discussion of the subject may be postponed. 
It may, however, be added that about six other spikes are showing, also 
spikes on the secondary hybrids between E. Xx kewense and both its 
original parents, while E. X kewense is already in flower, so that there 
should be some interesting material for comparison very shortly. Both 
these secondary hybrids produced weak spikes last year, but the results 
were held over in the hope that this year a more definite opinion of the whole 
problem could be formed. It would be interesting to self-fertilise E. x 
O’Brienianum, for the parents show well-marked differences, both in floral 
and vegetative characters. R. A. ROLFE. 
-_——————_ og 9 
