230 
A nalysis of Books. 
[April, 
Ouv Insect Allies. By Theodore Wood. London: Society 
for Promoting Christian Knowledge. 
The author of this work takes extreme ground. Along with 
very instructive lessons, he ventures to assert “ that not only is 
no insea absolutely injurious to our interests, but that there is 
none which, were we fully acquainted with its life-history, might 
not in some manner be utilised for our advantage. We are 
entirely with him when he points out the benefits which certain 
species confer upon us, and when he pleads for their protection 
It is always painful to us when taking a morning walk to notice 
the number of such useful creatures as Carabs and Geotrupes 
which the British workman has crushed when on his way to his 
daily employment. But we must never forget that the great 
claim of many species— not merely inserts, but animals in 
general — is that they rid us of others. 
Mr. Wood says “ If by a single word, for instance, we 
could sweep the Aphis or the cabbage-butterfly from the face of 
the earth, that word ought never to be spoken.” Now the 
damage done by the Aphis and the cabbage-butterfly is so 
immense that if it is to be compensated, and even outweighed, 
by any services rendered, those services would have to be ot 
corresponding magnitude, and could scarcely be overlooked. It 
is in vain to talk of their life-histories requiring to be better 
understood. The Aphis and the cabbage-butterfly have been 
most minutely studied,— the latter, for instance, in Herold s 
“ Entwickelungs geschichte der Schmetterlinge,” but no re- 
deeming feature has come to light. They do not destioy any 
hostile species ; they do not remove putrescent matter. In fact 
there seems to be no chink or cranny left for any benefit to us. 
Nor do we find any evil increase when and where they are rela- 
tively scarce, and decreasing, on the contrary, when and where 
they are numerous. It is very true that we occasionally discover 
some small redeeming feature in the character of such beings as 
the earwig, in illustration of the old proverb “ It’s an ill wind 
that blows nobody good.” But quite as often we discover that 
our animal allies are untrustworthy, and that our enemies have 
worse attributes than we could formerly have conceived. 
Thus Mr. Wood tells us that the good offices of the gnat— 
and we should presume of all its congeners far outbalance its 
bad qualities. Now did these creatures spend their whole lives 
in the water, there would be some grounds for this assertion ; 
but during their aerial life they not merely make man and various 
warm-blooded animals miserable alike in polar and in tropical 
regions but they are the artive propagators of disease ; the 
liquid which they instil into our blood, when biting, is a septic 
poison. 
