THE ORCHID REVIEW. 119 
CYPRIPEDIUM xX TACITA. 
Raised in the collection of H. Graves, Esq., of Orange, New Jersey, 
U.S.A., from C. x Measuresianum and C. tonsum. The flowers are large, 
five inches across, waxy, and of a sepia-green tint shaded with vinous-brown. 
The dorsal sepal is veined with brown and margined with white, and the 
petals have a brown line down the centre.—K. M. Grey in Garden and Forest, 
March Ist, p. 105. 
CyPRIPEDIUM X HEBE. 
A handsome hybrid raised in the collection of H. Graves, Esq., of 
Orange, New Jersey, from C. Spicerianum ¢ and C. x Stonei. It is most 
like the former, but the flower has a more graceful shape. The reflexed 
dorsal sepal is white with a green base and purple mid-nerve ; the petals 
two inches long, acute, undulate, primrose-yellow shaded with brown ; 
the lip apple-green tinted with brown in front, and the staminode lavender- 
purple with a yellow disc.—R. M. Grey in Garden and Forest, March ist, 
p. 105. 
CALENDAR OF OPERATIONS FOR APRIL. 
By W. H. WHITE, Burford, Dorking. 
ONE of the principal causes of spot and disease among Orchids is imperfect 
and insufficient ventilation. It is therefore of great importance to all those 
who have the management of a collection to see, not only that each division 
is properly ventilated, but also that no great fluctuations of temperature 
occur. During the month of April great vigilance will be required on the 
part of the cultivator, as with the numerous sudden changes in the ones 
temperature it is almost impossible to keep up a regular temperature in the 
houses, either by day or night. Should the weather be cold or boisterous, 
little or no air will be required, as sufficient will pass through the laps - 
the glass and under the doors, but when the mornings are calm and bright, 
the bottom ventilators may be slightly opened, and as the inside temperature 
tises, gradually increase the amount of air and moisture. For several hours 
during the middle of the day, it is advisable to allow each division to become 
comparatively dry. This partial drying of the atmosphere will allow the 
Plants to throw off any excess of moisture, which if retained would probably 
Cause decay. If the external temperature at this time is above 50°, air 
Should be given, by opening the ventilators on the sheltered side of the 
house. 
In houses where Orchids do not thrive quite satisfactorily, much good may 
often be done by careful ventilation. A case in point came unee my ~ 
a few years ago. A span-roofed house, containing principally Cattleyas, 
