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of caustic soda, and 5 quarts of water. This was applied when the 
trees were in a dormant condition. 
In the report of the same board for 1889 a reprint is given of Com- 
stock's description in an article upon scale insects and remedies. Sev- 
eral formulae for summer and winter use are given, the most successful 
of which, and the one which has come into most general use, being the 
so-called lime- sulphur- salt wash for winter use. This wash consists of 
40 pounds of unslaked lime, 20 pounds of sulphur, 15 pounds of stock 
salt, and water to make 60 gallons. The summer washes comprise pot- 
ash and caustic soda, whale-oil soap and sulphur, with a slight admix- 
ture of caustic soda and potash, and a mixture of tallow and resin with 
a small quantity of caustic soda and potash. In the report of the 
board for 1891 Mr. Alexander Graw published an article entitled 
"Insect pests and their extermination," in which he briefly discusses 
this species. He considers it to be a very serious pest of deciduous 
trees, but states that the remedies just mentioned are so cheap and 
effective that no excuse can be tolerated for a seriously infested orchard. 
He further stated that a Chalcidid fly (Aphelinus fascipennis Howard) 
had been found doing such effective work in subduing the species in an 
orchard in the neighborhood of Los Angeles that a complete restora- 
tion of the orchard was confidently expected. 
In Bulletin 26 of this Division Mr. Coquillett, in his report on the 
scale insects of California, devotes four pages to this species.- He states 
that its origin is uncertain, but that the fact of its being so frequently 
found upon plants imported from Japan would seem to point to that 
country as its original home. He states that the species never attacks 
citrus or coniferous trees, and that the LeConte Pear, when growing 
in the midst of other varieties of Pear, is almost exempt. The Twice- 
stabbed Ladybird (Chilocorus bivulnerus) is mentioned as being the 
most abundant and efficacious enemy of the scale, although Mr. Coquil- 
lett has never known an instance where even one single tree has been 
entirely or very nearly freed from the scale by the work of this beetle. 
The article concludes with a series of experiments with washes. The 
result of these experiments was that the resin and caustic soda wash 
recommended by Mr. Coquillett in Bulletin 23 of the division was found 
to be superior to the others. This wash is to be applied only during 
the dormant season, and consists of 30 pounds of resin, 9 pounds of 70 
per cent caustic soda, 4 J pints of fish oil, and water to make 100 gal- 
lons. 
Mr. Coquillett's testimony as to the good offices of Chilocorus bivul- 
nerus coincides with that of other observers, but a surprising instance, 
which indicates that the species may occasionally prove extremely 
effective, was mentioned iu the California Fruit Grower in 1892. It 
was there stated that Mr. N. W. Motheral procured a number of these 
beetles in San Diego County [date not given] and placed them in some 
orchards in Tulare County which were badly infested with the scale. 
They did not appear to multiply greatly until the spring of 1892, 
