December 3, 189L ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
469 
islands, and many of them are haunters of flower gardens where 
their presence should he welcomed. We cannot estimate with 
exactness the benefits we receive from them, as their victims 
cannot be numbered, but no doubt these natural enemies of our 
•garden pests accomplish results which would contrast favourably 
with the destruction of insects brought about by human agency. 
One notable circumstance in their economy is that by a sort of adjust¬ 
ment, if caterpillars or grubs are particularly abundant, Nature 
brings rapidly into existence in most cases a proportionate number 
of their destroyers. This was very observable in what some people 
■called the “ caterpillar year,” viz., 1887, when the warm dry 
summer much favoured these insects. Of many species there 
must be several broods during each season ; but we notice the flies 
chiefly while the sun is shining, as they not only hover about ; it is 
also their habit to run rapidly over plants, constantly vibrating the 
antennae. Some of them extract honey from flowers, only, how¬ 
ever, in small quantity ; they do not seem to need much food 
while in the fly state. 
Amongst the ichneumon flies we find great differences of size. 
Several are large, like Ophion, which is almost an inch in length 
and moves with a hum, the bulk are of moderate size. Some, and 
these of considerable use, are very small, having also short wiDgs ; 
they might be taken for little ants upon the twigs or leaves. 
Generally, we might say these flies are examples of lightness and 
strength. The thorax is stout, the abdomen long and slender, usually 
attached by a stalk, in the females having an egg placer ; the wings 
are delicately veined, often large, and the slender antennae show 
keen sensibility to touch ; it has been supposed they may be also 
organs of hearing. Some of the ichneumon flies deposit but a 
single egg on each victim, and some fasten upon it a number, even 
seventy or eighty have been counted. When full fed some of the 
larvae (which are all maggot-like, only they have six minute legs) 
change to pupae within the carcase oil their victim, from which they 
emerge as perfect flies. Most quit it and spin a cocoon of silk ; this 
is sometimes beautifully banded with colours, a peculiarity 
observable by a moderate magnifying power. One species of 
Microgaster is seen to form its cocoons in tiers, the larvae working 
together when they have fattened on some caterpillars, twenty or 
more cocoons being joined so as to resemble a honeycomb in 
miniature. Another Microgaster groups the cocoons together 
irregularly ; these are like tiny half cheeses, and the larvae spin 
about them a sort of grey wool, possibly to keep off enemies. Then 
"there are cocoons which are swung, and some that are called jump¬ 
ing cocoons, because they leap or jump about from the contortions 
of the pupa enclosed ; this may be because it is itself attacked by 
another insect, for there is ample proof that ichneumons are them¬ 
selves often preyed upon by other lesser parasites, fulfilling a 
familiar saying. 
Many a plump caterpillar, which has devoured the leaves and 
tender stalks of our garden flowers, holds within it the larvae of an 
ichneumon fly, by which its farther advance is arrested. We have 
a well-known instance in that of the small white butterfly, which 
is a feeder upon Cruciferous and other plants in our flower beds 
from spring to autumn. It is attacked by more than one ichneumon 
fly, notably by a species of Microgaster, allied to that, which first 
slays the common caterpillar of the Cabbage butterfly, then covers 
it with a mass of golden cocoons. It) is the habit of the grubs or 
larvae to feed within the caterpillar they infest, and manage to 
avoid a vital part till they have nearly become adult, when they 
finish it off, leaving but the shrivelled skin as a relic. The cater¬ 
pillar of the gamma, which feeds upon a variety of herbaceous 
plants, is checked in its increase by an ichneumon fly ; so too is the 
abundant caterpillar of the Currant moth, which occasionally pays 
a visit to our flower beds. Hairy caterpillars do not escape, such 
as those of the garden tiger and the common ermine. In spite of 
their clothing the flies succeed in placing eggs, and the larvae 
burrow into the skin. The repul-ive sawfly grubs, so hurtful to 
"the Rose and to other favourite plants, have their diligent foes of 
"the genus Paniscus. Even the tiny caterpillars that d'sfigure our 
shrubs by rolling their leaves have no power to elude these flies, 
which, by means of the egg-placer, reach them in their green hiding 
'place. 
In the Ophion group we have the singular circumstance that 
the eggs are laid upon the footstalks, not inserted in the skin, and 
the grub when it enters carries in a thread which keeps it attached 
to this stalk till it is adult. Some of the caterpillars infested by 
■Ophion grubs succeed in making their cocoons, but they do not 
enter the pupal state, the parasites’ cocoons being spun inside —the 
caterpillar’s dying effort. Then there is a large tribe of these flie3 
<called the Braconidm, and their occupation is different. They hunt 
up a variety of beetles, and deposit eggs on their hard wing-cases, 
but the larvae manage to pierce in, and through them many beetles 
that gnaw leaves or nibble our flowers die off speedily. Great, too, 
•is our obligation to another group, the Aphidib These tiny flies 
deposit one egg upon the body of every aphis they attack, and 
diminish the numbers of one of our most troublesome insects. Each 
fly is parent of many larvae.—E ntomologist. 
LILY OF THE YALLEY FOR FORCING. 
A few sprays of Lily of the Valley during the winter months are 
much appreciated by all lovers of flowers, and especially when flowers 
are required for working into sprays for ladies, or for buttonholes. 
Although the Lily of the Valley is a hardy plant, it requites a high 
temperature to force it into bloom by Christmas and the following two 
or three months. We grow, and greatly prefer, single crowns for early 
forcing, as they come into bloom earlier and are more certain than 
clumps, although these are useful for later use. Many people have 
failed with crowDS ; but when failure occurs it is due to their being 
allowed to become dry before potting, or keeping them too diy during 
Fig. 87.— forcing lilies of the valley ; a pot of single 
CROWNS. 
forcing. If procured from a respectable nurseryman the crowns are 
sure to be well ripened and in a fit state for potting on arrival. 
If it is not convenient to pot them at once cover them over in damp 
cocoa-nut fibre refuse in the open air until the desired time arrives. 
We place sixteen crowns in a 5-inch, or 48-size pot, and insert them very 
firmly, arranging them equally over the pot with the tips of the crowns 
protruding through the soil. Some people find a difficulty in arranging 
them in the pot, but by placing the required number in the hand with 
layers of soil between they can be dropped in and the rest of the soil 
worked in amongst them. 
After potting, plunge in damp cocoa-nut fibre refuse in a cold frame, 
or in the open air. Although they may be introduced for forcing 
directly after potting, we do not place ours in heat until two or three 
weeks afterwards, when they are introduced as required. From three to 
four weeks generally elapse from the time of placing them in heat 
until they come into bloom, if the course of treatment is puisued that 
will be here indicated. A moist bottom heat of 90° is required, and a 
position where they may be kept quite dark. 
We have a small frame placed overlfhe pipes where they enter the 
house, and this is kept covered up so as to keep the interior dark. When 
