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size and abundance, was thé nine-spotted lady bug ( Coccinella 9-notata). It 
may be recognized by the arrangement of the nine black spots on the brown 
wing covers—four on each side, the ninth just behind the thorax and overlying 
the middle line. It is very nearly a half sphere in shape. The other species are 
like it in general shape, but differ in details of colourand markings. A small list. 
of other insects which do more or less good in destroying the aphides could be 
given, but this will suffice to give an idea of the more abundant and useful of our 
insect friends. 
Birds have been thought to destroy the lice, but I have seen no evidence of 
their doing so. Most birds depend on larger insects, and it is only occasionally 
that the small species, such as warblers, eat plant lice of any kind. Excepting 
the Maryland yellow-throat, birds of this family rarely occur in our grain fields, 
so that we can hope nothing from their help. The English sparrow, with its 
clumsy beak and grain-eating propensity, certainly does no good in this direction. 
EXPERIMENTS WITH ARSENITES.—In the Bulletin of the Iowa Agricultural 
Experiment Station for August, 1890, Prof. Gillette gives an elaborate and inter- 
esting account of a series of experiments that he carried out for the purpose of 
testing the use of a1senites in the warfare against noxious insects. 
‘Paris green, he says, was brought into prominence as an insecticide for the 
first time in this country in 1869, and London purple in 1877. Arsenious acid 
(white arsenic) was successfully used for the destruction of the Canker-worm as 
early as 1875 and is still frequently recommended for the destruction of insects. 
During these years the arsenites have arisen to the first rank as insect destroyers. 
They have been largely experimented with by entomologists and widely used by 
farmers and fruit-growers, and yet there is much difference of opinion as to the 
proportions in which each may by safely applied to different plants for the des- 
truction of insects. In fact a serious obstacle in the way of a more free and 
successful use of the arsenites has been their liability to injure tender foliage, 
even when applied very dilute. In the experiments of the past two seasons, 
herein reported, I have given much attention to the finding of some method of 
applying these poisons so as to prevent injury to foliage without lessening their 
effectiveness in destroying insect life, and the success met with in this direction 
has been most gratifying. I also give the results of experiments to determine rela- 
tive injuries to foliage from applications of the arsenites when freshly mixed and 
when allowed to stand a few days before being applied; to show the effect upon foli- 
age by adding paste or soap to arsenical mixtures; to show the effects of sun, dew 
and rain upon foliage treated with arsenical mixtures; to show whether or not. 
it is practical and safe, so far as injury to the plant is concerned, to mix the ar- 
senites with insecticides that kill by external contact ; and to show the effects of 
combining the arsenites with fungicides.” ok 
After giving a detailed account of his various experiments, he arrives at the 
following conclusions :— =~ - 
“I. The oldest leaves are most susceptible to injury from arsenical applica- 
tions. They often turn yellow and drop without showing the burnt spotted 
appearance.* 
2. Dews, and probably direct sunlight, increase the injuries done by the 
arsenites to foliage. 
* [have put in italics those conclusions that seem to me to be well proven from the experiments here 
reported. Concerning the others there is some doubt, and further experiments are necessary to determine > 
positively the facts. 
