ACARUS. 
103 
= 
ACHILLEA. 
when Acacias are kept in a green- 
house adjoining the living-rooms of 
a house, care should be taken to 
give the house abundance of venti- 
lation ; and this is also very con- 
ducive to the health of the plants. 
Aca‘cta.—See Roginra, Mimosa, 
and Inea. 
AcantTuopur prium.—Orchidacee. 
—A curious orchideous plant, which 
may be grown in pots, in peat and 
loam, allowing it a season of com- 
plete rest, as soon as the leaves | 
wither, by putting it in a cold house, 
and withholding water for two or 
three months, and then supplying it 
abundantly with heat and moisture 
when the plant begins to shoot. 
Aca’nruus.— Acanthdacee.—Per- 
ennial plants, natives of the warm 
parts of Europe, two of which, A. 
mollis and A. spindsus, deserve a 
place in every collection, from their | 
stately appearance, and from the 
legend of their leaves having given 
the first idea of the capital of the 
Corinthian order of architecture. 
All the kinds of Acanthus require 
a sandy soil, anda good deal ofroom ; 
and they are all readily increased 
by division of the root, and by seeds. 
The situations most suitable for a 
large plant of Acanthus are near a 
stone seat on a lawn, at the foot of 
a block of stone introduced among 
rockwork, or among classical ruins, 
such as those at Virginia Waiter, 
Windsor, &c. In a garden at 
Hammersmith, a fine effect was pro- 
duced, some years since, by a noble 
plant of Acdnthus spindsus spring- 
ing from the base of a shattered pe- 
destal, and half concealing the 
broken statue that had fallen from it. 
A’carus——A genus of small in- 
sects or mites. A’carus telarius, the 
red spider, is one of the most trou- 
blesome of all insects to gardeners, 
particularly in the bark-stove, as it 
breeds in the bark. When first 
yellowish green, and it spins its web 
on the under side of the leaves. As 
it gets older, it becomes of a brown- 
ish red. It bas eight legs, and be- 
longs to the spider family ; but it is 
provided with a kind of proboscis 
or rostrum, with which it sucks the 
juices of the leaves it lives upon, and 
soon withers them; thus spoiling 
both fruit and flowers, as neither 
can attain perfection unless the sap 
that nourishes them has been prop. 
erly elaborated in the leaves. It is 
very difficult to destroy this insect, 
as tobacco-smoke, and the other 
‘remedies generally used against it, 
appear to have very little effect. 
Sprinkling with cold water will some- 
times destroy it; but, as the insect 
is generally produced by keeping 
the plants too hot, and not allowing 
them sufficient air, the best remedy 
appears to be to set all the hothouse 
| plants in the open ground during the 
months of July and August, plung- 
ing the pots ina bed of dung, de- 
cayed leaves, or tan, and well ven- 
tilating and cleaning the houses 
while they are empty. 
ACHILLE’ s. — Compésite.—The 
| plants belonging to this genus are 
known under their English name 
of Milfoil. Most of them have no 
great beauty, but they are of very 
vigorous growth, and will thrive in 
any soil or situation, bearing either 
smoke or ccld without any visible 
change. They are also suitable 
plants for balconies or boxes, as they 
are not easily injured either by too 
much watering, or by being kept 
teo dry. The most ornamental of 
the vigorous-grewing kinds are 
Archilléa tomentosa, the woolly Mil. 
foil, with yellow flowers, and A. ta. 
nacetifolia with red flowers. Of 
the more delicate species, A. Cla~ 
vénne, the silvery-leaved Milfoil, 
with large white flowers, is a very 
pretty little plant for rockwork ; but 
hatched, this little creature is scarce- | it is rather difficult to keep, uniess 
ly perceptible, as its colour is of a|it be grown in a dry soil and a 
