May, 1914.] THE ORCHID REVIEW. 143 
ought not to be exposed to strong sunshine during the hottest months of 
the year. 
The two finest species are P. simulans and P. tuberculosus, and the 
former has participated in a splendid series of hybrids, which flower from 
March till May. Little difficulty is experienced in growing the hybrids, 
but the species quoted do not respond very readily to the conditions 
prevailing in our Orchid houses. They hail from Madagascar, and require 
a few degrees more warmth than the other members of the genus. P. 
simulans is often tied to a raft with the base placed in a pot or pan, and 
very little, if any, loam is needed in the compost. Where growers happen 
to possess a few plants it is advisable to try them in different positions, for 
up to the present their cultural requirements are not fully understood. A 
few years after being imported they gradually deteriorate, and eventually 
die, a fate which overtakes some other Madagascar Orchids ; for example, 
the scarlet-lipped Cymbidium rhodochilum, which in all probability is only 
represented by dried specimens in this country at the present time. 
Mexican Laias.— Where these Lelias were not given fresh rooting 
material earlier in the year, the present month is a suitable time to do any 
necessary repotting or top-dressing. Pans or teak-wood baskets may be 
used as receptacles, which should be amply drained. The compost consists 
of osmunda or Ar fibre, with a sprinkling of chopped sphagnum moss. No 
Orchid will succeed unless it possesses a fair amount of live roots, but with 
L. anceps and its allies the general treatment, such as_ ventilation, 
temperature, light, and resting plays a most important part in their 
Successful culture. A‘ separate house is often set apart for this class of 
plant, but a good substitute is the lightest end of the Cattleya division, 
where they may remain during the growing season, and receive all the light 
possible short of scorching the foliage. A moist atmosphere is essential, 
and the plants can be sprayed overhead whenever the weather is suitable. 
It is advisable to give the house a thorough damping down when the blinds 
are removed early in the afternoon, closing all the ventilators at the same 
time. These may remain closed until the evening, when an inch or so of 
ventilation will allow any superfluous moisture to escape. Water should 
be freely given when the roots have taken possession of the soil, and an 
average temperature of 65° F. maintained, but with sun heat these figures 
can be exceeded and no harm will accrue. The principal factors in the 
culture of Mexican Lelias are plenty of light, air, and moisture during 
their active period, and a decided rest after the pseudobulbs are fully 
matured. One of the probable causes of failure is that the plants are not 
sufficiently rested, and are invariably started into growth too early in the year. 
OpontocLossum ciTRosMUM.—This Mexican Odontoglot will require 
attention at the base directly the flower scapes are removed. It should be 
