422 Reporr oF THE DEPARTMENT OF ENTOMOLOGY OF THE 
of the concentrate diluted with eleven gallons of water, while 
not so effective, greatly reduced the amount of breeding, and 
cleaned the bark of many of the older scales. The adhesive- 
ness of the clear solution was noticeably superior to that of 
the sediment. 
Series [1.—This comprised a number of miscellaneous ex- 
periments, repeated at various intervals, with sediment from 
which the soluble sulphur compounds had been removed by de- 
cantation. This was applied at different consistencies by mix- 
ing with one or more volumes of water. For purposes of com- 
parison many other trees, similarly infested with scale, were 
thickly painted with calcium sulphite, calcium sulphate, and 
lime paste. Some small trees growing in a greenhouse were 
given the same treatments to facilitate closer observations on 
the movements of the young scales. 
Results on the scale.— The trees that were grown in the open 
field exposed to the usual conditions of weather were practi- 
cally free of the heavy coating before the appearance of the lice, 
although the bark showed some discoloration by the treatments. 
Trees similarly painted with these materials but which were 
grown in a greenhouse, free from the influences of weather, re-_ 
tained their coatings intact for a long time after breeding com- 
menced. None of the applications made to the trees growing 
in the open and subjected to normal weather conditions effi- 
ciently controlled the scale. The lime-sulphur sediment, cal- 
cium sulphite, calcium sulphate and lime wash, applied as a 
rather thick paint to form an appreciable crust on the bark, 
removed, on weathering off, some of the old scales, but in no 
instance did the treatments prevent considerable production of 
young scales. 
Of the experiments in the greenhouse, the applications of 
these same materials, using them in the consistency of thin 
paint, had no important effect in reducing the numbers of 
young scales. The trees, however, which continued to be 
thickly coated with the application at the time of breeding, 
were generally exempt from new infestation. Large numbers 
of the mature females were able to project the posterior por- 
