186 THE ORCHID REVIEW. [JUNE, 1906, 
moist atmosphere. These two and a half hours of closeness constitute the 
only period out of the twenty-four that the houses are entirely without air 
—from 3.30 to 6—and at six the re-opening of the bottom ventilators will 
again start the air in circulation. A genial warmth must be kept in the 
pipes all night, not so much for the sake of the heat, which, during many 
nights, will not be required, but to keep the air on the move. This is 
really a very important point in the summer growing of Orchids. In the In- 
termediate or Mexican Houses, when the night temperature is above fifty-five, 
one might with safety allow the pipes to become cold, but air should not be 
reduced in consequence of that, but quite the reverse. We do not generally 
put top air on our Cattleyas at night thus early, unless the weather be very 
close. Air, top and bottom, should now be nearly constantly on in the 
Odontoglossum house, and no, more artificial heat should now be wanted 
until the summer is over. 
TEMPERATURES.—The temperatures for the next month or two will be 
easily maintained, but one must always be on the watch for cold snaps, 
which are not infrequent. The East Indian house should not be allowed to 
fall below 70° at night, with a rise of 5° to 10° during the day ‘in sunless 
weather. More frequently than not these temperatures will be exceeded, 
but one should not strive after a much higher night temperature. The 
Cattleya house may drop at night to 65°, and even to 60° in the morning, 
and the Intermediate house 5° lower. It is not so much a question of the 
actual temperatures, as of, literally speaking, good breathing conditions. 
We learn that in the forest the dew falls at night, and that the plants 
become saturated, but I should not advise this to be copied at home, with 
perhaps some reservation in the case of Odontoglossums. A stagnant night 
atmosphere is bad, even when warm; when cold, of course, it is much more 
dangerous. The Odontoglossum house should not now be allowed to drop 
much below 55°, and it may be necessary now and again during the summer 
to turn on a little heat in this house. 
ODONTOGLOSSUM SEEDLINGS.—-These are making very good progress 
now. Two-year-old plants are finishing up their first pseudobulbs, and the 
leaf expansion in these will now be less marked than it has been for some 
months. In many cases the pseudobulbs are finished, and the new growth 
has started. When these new growths are about two inches high, the 
plants may, if they are in want of it, be repotted. The first pseudobulbs 
not flowering, the new growths shoot immediately—sometimes even before 
the pseudobulb is finished—and will grow very well all the summer, if the 
temperature is kept well down. They grow best during the summer ina 
temperature of 65° by day and 60° by night, in a steady, buoyant, moist 
atmosphere. Small Odontoglossum seedlings will stand very little sum 
shine, and great care must be taken, especially in the morning and the 
i 
a 
ee 
