f
heat and moisture should be gradually increased. Directly they have
flowered, the tall plants which have lost their bottom leaves should be
lowered in the pots or baskets by being cut off at the base.
Dwarf-growing species should be brought well up to the light. _V.
coerulea_ grows well under the most dissimilar conditions, and with
it, as with many other Orchids, there is more in finding a suitable
place than in growing the plant. All require to be potted or basketed in
Sphagnum-moss. Some growers add a sprinkling of leaves. The _V. teres_
section may be planted in Sphagnum-moss in a warm corner of the house,
or against the end of the house. If grown in pots, three or four should
be potted together and trained to a stout stick or teak rod.

~Zygopetalum.~--Under Zygopetalum, several distinct sub-genera are
included. The largest-growing and showiest species include _Z. Mackayi_,
_Z. crinitum_, and other related species. These should be potted in
peat, Sphagnum-moss, and loam fibre in equal proportions, with a
sprinkling of leaves, and fine broken crocks added. During the growing
season occasional waterings with weak, liquid manure should be given;
and, after flowering, a rest with restricted water supply. Those that
need repotting should be attended to before growth begins, but they will
remain satisfactory for years in the same pots if carefully treated.

There are many hybrids, especially of _Z. maxillare_, which should be
treated like the species. _Z. rostratum_ requires a warm, moist house.
The Promenaeas include _P. stapelioides_, _P. Rollissoni_, and _P.
xanthina_. These should be grown in shallow pans, either for suspending
or placing on a shelf near the glass of the roof.

~Bollea~, ~Huntleya~, ~Pescatorea~, ~Batemannia~, ~and~
~Warscewiczella~.--These are sectional names for a leafy class, with
rudimentary pseudo-bulbs. They are frequently mismanaged. The plants
should be grown in the potting materials recommended for epiphytal
Orchids, and surfaced with Sphagnum-moss. Being evergreen, and with no
superabundant vitality, they should be kept moist all the year, but
liberally watered when growing. A moist corner of the intermediate
house, or warm house, should be selected for them, each plant being
raised on an inverted pan or pot. When grown in the warm house, a rest
should be given in a cooler house after growth is completed, but the
plants must not be dried off. They may be propagated by division. All
req