268 
THE CULTIVATOR. 
Sept. 
when applied in the liquid state, the benefit is most ap¬ 
parent. 
Ought any other substances to be mixed with 
Dissolved Bones ?—Bones are known to exercise a 
comparatively feeble action upon stiff and undrained 
clays, and it may, therefore, be reasonably asked by 
some if the action of dissolved bones will be more cer¬ 
tain upon such soils than the bones in their natural 
state ? We may, I think, answer this in the affirma¬ 
tive. since the principal cause of the less conspicuous 
effect of bones upon such soils is to be found in their te¬ 
nacity and coldness, by which the particles of bone are 
shut out from the air, and their decomposition is retar¬ 
ded. 
But inasmuch as bones do not contain the whole of 
the substances which plants require, and as some of 
those which are present in bones, the salts of soda, for 
example, are in small quantity only, it may be reason¬ 
ably asked again, if the dissolved bones would not be 
improved, and their efficacy increased, and rendered 
more sure , were an addition of certain substances to be 
made to them. Of this I think there can be little 
doubt, though the necessity and nature of such addi¬ 
tions will depend much upon the nature of the soil to 
which they are to be applied. A small per centage of 
pearl ash or wood ashes, of nitrate of soda, or com¬ 
mon salt, and a sulphate of magnesia—-5 lbs. each of 
the potash and soda salts, and 10 lbs. of the magnesia 
salt to each 100 lbs. of bones—would render the mix¬ 
ture more suited to every soil and crop. At the same 
time, if the soil, like those formed from the felspar 
rocks, abound in potash, or like those which border the 
sea, be rich in soda, or like those which owe their ori¬ 
gin to the slates, or to the magnesian limestones, con¬ 
tain already too much magnesia, any addition to these 
several substances would obviously be thrown away. 
The principle of adding such things being recognised as 
sound, the knowledge and discretion of the farmer must 
be exercised in determining how far such additions are 
likely to be profitable, or he may make a small preli¬ 
minary experiment by way of trial. 
In conclusion, I may remark that the more extended 
use of this mode of preparing manures—creating, as 
it must, an increased demand for sulphuric acid, and 
consequently for the raw materials from which this 
acid is manufactured—will exhibit another illustra¬ 
tion of that intimate connection, which must always, in 
a healthy state of things, exist between the agricultur¬ 
al and the manufacturing and the mining interests, and 
of the certainty with which the advancement of these 
interests must lead to the greater extension and pros¬ 
perity of every other department of the national industry. 
HABITS €F IN§I3€T§ S 
The remarks of a correspondent of the Cultivator , I 
under the head of “ Spare the Spiders,” suggest the 
importance of a knowledge of the habits of insects. 
The innumerable number of these, and the immense 
consequences depending upon them, are seldom proper¬ 
ly considered. Many tribes attack the crops of the 
farmer, which fail more frequently from this cause than 
any other, except, perhaps, the effects of unfavorable 
weather. Famine and pestilence have at several peri¬ 
ods ensued from their devastations in various parts of 
the Eastern Continent, and even in our own country, 
they have often occasioned great losses and no small 
amount of human suffering. The “staff of life” has been 
nearly cut off in many instances, by the attacks of that 
tiny depredator, called the Hessian fly, and Vs equally 
insignificant congener, the wheat midge. Various 
crops have been destroyed by the wire-worm, the cut¬ 
worm, and the grasshopper ; our fruits have been blast¬ 
ed by the caterpillar, the canker-worm, the curculio, 
and the aphis; and even the trees themselves destroyed 
by the insidious workings of borers and worms. Other 
species, again, prey on our domestic animals, and some 
directly attack, annoy, and injure the human race. 
The more we know of these formidable enemies the bet- 
ter we can protect ourselves against their ravages. And 
in this view of the subject, perhaps there is no one fact 
of greater importance than this: nearly every species 
of insect that is injurions to man, is preyed upon and 
destroyed by some parasitic or predacious enemy. How¬ 
ever revolting, at the first thought, may appear this 
system of perpetual warfare among the tribes, it is evi¬ 
dently a wise and benevolent principle, calculated to 
preserve the proper balance in this department of or¬ 
ganic life, and affording proof that 
“ Nature’s differences are Nature’s peace.” 
In regard to one of the most destructive insects to 
the farmer, the Hessian fly, (to which allusion has been 
made,) its natural enemies are an important cheek to 
its increase. “ Other insects,” says Dr. Fitch, “have 
been created apparently for the very purpose of preying 
upon this, and thus preventing it from becoming inordi- 
nately multiplied.” 
There are several species of these ichneumons , as 
they have been named, but one called the Cerapkron 
destructor, is the most common. It is a small bee¬ 
shaped insect, not much larger than the Hessian fly, 
and in the spring may be sometimes seen in great num¬ 
bers in wheat fields; and the circumstance that it is of¬ 
ten mistaken by farmers for the “ fly” itself, strikingly 
exemplifies the necessity of understanding the economy 
of insects. 
This ichneumon attacks the “ fly” while in the “flax¬ 
seed ” state, the latter lying dormant encased in a co¬ 
vering, which resembles in form and color, a flax-seed. 
It is between the stalk of wheat and the surrounding 
sheath. Instinct enables the ichneumon to know where 
its prey is lodged; it punctures the sheath, and deposites 
its egg in the body of the larva; the egg hatches and be¬ 
comes a worm, which preys upon and destroys the lar¬ 
va of the “ fly.” It is thought by some naturalists, 
that at least nine-tenths of the larva of the Hessian 
fly are destroyed in this way. 
Another very minute parasite of the Hessian fly, 4 
species of Platygaster, according to Prof. Herrick, de¬ 
posites its own eggs in those of the “ fly.” The latter 
hatch, and the worms pass into the flax-seed state with 
the young parasites in them, but they are destroyed be¬ 
fore the next transformation is effected, and the parasites 
leave the shell. 
Your correspondent before alluded to, has well illus¬ 
trated the usefulness of spiders in destroying the trouble* 
some house-fly, and in other respects. There are, how¬ 
ever, several species of field-spiders which devour great 
numbers of crickets, grasshoppers, various kinds of 
moths, butterflies and beetles. If, towards the latter 
part of summer, we look at the surface of a meadow 
or stubble-field, early in the morning, while the dew is 
on and the sun is shining brightly, it will appear to be 
almost covered with spiders’ webs. On examination, 
nearly every web will be found to have one or more of 
the above named insects in it, lately caught; and this 
ratio of destruction is carried on daily, through several 
weeks of the season. 
The artful sagacity of the spider is in no case mct% 
