a THE ORCHID REVIEW. (Marcu, 1915. 
O. Adrianz, more or less continuously, to O. Hunnewellianum, doubtless 
the result of crossing by insect agency through innumerable generations, 
Artificial hybridisation will probably throw more light on this interesting 
question in the future. Much has already been done, and a few well 
directed experiments might solve some of the points that still remain 
doubtful. 
CALENDAR OF OPERATIONS FOR FEBRUARY. / 
By W. H. Wuirr, for many years Orchid Grower to the 
VO 
Jate Sir ‘l'revor Lawrence, Bart; KC 
HADING.—The season of the year has now arrived when it is necessary 
to have the blinds or shadings used on the houses fixed in their places 
at once, ready for use at any moment, for the sun is now getting too 
powerful for some Orchids, especially where the houses are so situated that 
it shines directly on the plants. In the coolest division, particularly span- 
roofed structures running north and south, the temperature, under the sun’s 
influence, quickly rises above what is necessary to grow the plants to the 
highest perfection. This will certainly be the case on clear, bright, cold 
days, when the external air, being, perhaps, several degrees below 40°, is 
unsuitable to be admitted with sufficient freedom to keep down the 
temperature. At such times the blinds should be used. If the external 
air is congenial, that is, above 50°, and moist, give abundance of air and 
shade less. The blinds on the East Indian, Cattleya, and Intermediate 
houses will only have to be let down for an hour or so over those roofs 
which fully face the sun. The blinds for the Cool house and the two last- 
named divisions should, when down, be five or six inches above the glass, 
the benefit of which to Orchid-growing is very great, but those of the East 
Indian house may be rolled down on the glass, as a maximum of sun-heat 
is necessary for the majority of the plants in this division. The Mexican 
house should be very thinly shaded, but the inmates will need no protection 
until the sun gets really strong, as the plants delight in an abundance of 
sun-heat and light at all times. 
ight, to thoroughly examine the new glass for flaws, or if 
the offending pane, or the flaws only, with white paint. 
PREPARING CoMPOsT.—For the next fe 
importance will be Tepotting many of the 
renewing the surface of those which do 
w months the work of great 
plants and young seedlings, or 
not need the former operation. 
