ause the old
large specimens are replaced by young and vigorous plants. Thirty or
forty years ago, it was a usual thing to spend several days every year
scraping the brown scales from tall plants of _Aerides odoratum_, _Vanda
tricolor_, and other specimen Orchids, and what was called "cleaning"
was going on all the year round. Now there is much less need of such
work, although scale will appear in its various species on one section
of plants or another. In the periodical inspections, all plants attacked
by it should have the insects removed by a piece of stick blunted at the
edge and point, sponging the leaves afterwards with some diluted
insecticide. Syringing with an insecticide, or dipping the plants in the
liquid, should be avoided, for the quantity applied is likely to
saturate the material in which the plants are potted and to run into the
centres of the young growths and cause injury. By means of a sponge, it
may be applied lightly or heavily, but the operator has command in each
case over what he is doing.

MEALY BUG

Fortunately this pest is rare in Orchid houses, but when it appears it
is easily destroyed in the same manner as scale.

COCKROACHES

The first of these insects to be noticed should be the signal for the
laying of poison. Search should be made for the breeding quarters, which
are often in the stoke-hole, or in some hot, dry corner of the house.
Various preparations are recommended, but the best still seems to be the
old phosphor paste, which should be placed on pieces of paper in the
haunts of the insects in the evening, and removed the next morning, a
fresh supply being put down every two or three days so long as one of
the insects remains.

SLUGS, SNAILS, AND WOODLICE

To combat these is more a question of diligence than anything else. The
old remedies to attract them, such as lettuce leaves, or hollowed halves
of potatoes, are still effective, and a walk round the houses with a
light at night never goes unrewarded.

CHAPTER XIII

PERIODICAL INSPECTION

Whenever the time is to be spared, it is a good plan to overhaul one or
other of the sections of Orchids thoroughly, and to have a more general
inspection as soon as possible after the winter has passed, and at the
end of the summer, this latter inspection being the more important.
Cleanliness in everything around Orchids is one of the most important
aids to successful culture, and, during the periodical inspections,
pla