SHADING 21 
all the varieties of Cypripedium insigne, C. Spicerianum, 
C. Charlesworthii, and all the green-leafed section known 
as Selenipediums, will thrive admirably, and a very large 
selection of other showy Orchids, including Zygopetalums ; 
but again I would say that species which are usually re- 
garded as warm-house Orchids must be rejected. 
SHADING 
It should be distinctly understood that every Orchid 
house needs to be fitted with proper means of shading, 
extending over the whole roof and removable when necessary. 
Some cultivators think they meet the case by providing 
shading only on the sunny side, or by painting the glass 
with some kind of preparation more or less in the nature of 
whitewash. Such preparations should never be used, be- 
cause, when this is once placed on the glass, the shade, 
such as it is, is there in dull as well as bright weather, 
in the night time as well as the day, and for the greater 
part of the time, especially in dull seasons, it obstructs 
light which is necessary for the proper development of the 
plants. Another important objection to their use is that 
shading given by these washes wears off and leaves the 
plants exposed to the full sunlight. The substance is washed 
off by the rains and carried into the rain-water tanks, thus 
causing injuries to the plants watered with the polluted 
water, and rendering unsightly the foliage moistened with it. 
Proper blinds running on iron or wooden supports, raising 
them well above the glass of the roof, are absolutely neces- 
sary. Lath roller blinds are excellent for shading, being 
durable, clean, and easily let down and drawn up. 
