New York AGRICULTURAL EXPERIMENT STATION. 255 
notice. Observations and experiments wére made to ascertain the 
life history of the insect and to determine practicable methods of pre- 
venting important injuries. With a knowledge of its habits, it was 
reasoned that the insect could be controlled by spraying with an 
arsenical poison, provided the treatment was applied at the proper 
time, which should be when the buds are swelling and again as the 
leaves are making their appearance. 
With this in mind experiments were undertaken with paris green; 
and from the first the effect of the treatment was plainly apparent. 
From these tests it was concluded that the pistol case-bearer can be 
controlled by thorough applications of an arsenical poison, the treat- 
ments being made as the leaf buds begin to swell and when the 
leaves are unfolding. As bordeaux mixture was coming into general 
use for orchard treatment, especially for the apple scab, it was con- 
sidered advisable to employ this spray as a carrier of the arsenical, 
as neither interferes with the beneficial action of the other. 
Some tests were also made with kerosene emulsion, at a strength 
of one part of the emulsion to ten parts of water. Although the 
trees under treatment were badly infested with both the pistol case- 
bearer and a closely allied species, the emulsion seemed to have 
no effects on either insect. It was thought that a preparation con- 
taining larger percentages of oil would have penetrated the cases, 
but under the circumstances to use this was considered inadvisable 
because of the risks of injury to the tender foliage and flower buds. 
PLANT LICE. 
(A phididae.) 
In response to the demand for information concerning the nature 
and habits of these insects, together with the best known methods 
of combating them, a bulletin?! was prepared and distributed in 
1897. These lice are among the most important of the injurious 
insects. They infest all kinds of fruits, vegetables and ornamental 
plants. Although present every year, some seasons are more favor- 
able for their development than others. This season had been one 
of this kind and various species had caused serious injury to orchard 
and bush fruits. Experiments with whale oil soap in plum orchards 
and currant plantations had demonstrated the efficiency of this 
spraying mixture for plant lice, and were the basis for detailed 
directions in combating these well known pests. 
* Bul. 139; same in Rpt. 16:470-488 (1897). 
