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layer untouched ; next they form slight oval silken cocoons (b) 
within the burrows, and inside of these they change to chrysa- 
lids. When ready for the final change, each chrysalis wiggles 
forward, ruptures the thin layer of bark and pushes itself half- 
way out of the opening ; then the chrysalis shell breaks open 
and the moth emerges leaving the empty case behind it, as 
shown in d, Fig. 6. The moths emerge early in summer, and 
soon after deposit their eggs. 
Keeping the bark smooth and free from cracks or other inju- 
ries is an important preventive of the attacks of this insect. It 
is also stated that their injuries may be prevented by applying 
to the trunks early in summer a mixture of lye and soft soap, 
it being more effective if a little Paris green is added. Spray- 
ing the trunks thoroughly with the Bordeaux mixture and Paris 
green combination might prove an effective preventive. 
REPORT OF THE BACTERIOLOGIST 
During the year ending July i, 1895, this department has 
carried on the following work : 
In July and August, 1894, experiments were made in the treat- 
ment of the early blight of potatoes by spraying with the Bor- 
deaux mixture. The details and results of these experiments 
together with those of experiments begun previous to July 1, in 
the treatment of fungous diseases of pears and apples and the 
disease known as potato scab, were published in Bulletin No. 
27, April, 1895, of this station. 
After the burning of the station barn in November, 1894, the 
cattle composing the station herd were subjected to the tuber- 
culin test for tuberculosis. Seven animals were condemned. 
Of these two were killed immediately and found to have tubercu- 
lous lesions. The remainder were isolated and experiments were 
begun to ascertain if the germs of the disease could be detected 
in their milk. This work consisted in microscopic examina- 
tion, inoculation of guinea pigs, and the feeding of calves with 
the milk. In March, 1895, the herd was again tested and two 
