l8 FIRST REPORT ON ECONOMIC BIOLOGY. 



The following" simple sprayfluid was found very effective, indeed, 

 I know of nothing" better for the destruction of mites. In America 

 it has proved successful for treating" the Brown Mite (Bryobia 

 pratensis, Garman) and the Red " Spider " (Tetranychus bimacuhitus, 

 Harvey), when nicotine and other substances have failed. 



Flowers of Sulphur ... ... 16 Ibs. 



Soft Soap ... ... ... \ Ib. 



Water ... .. ... 50 gallons. 



The trees should be sprayed as soon as ever any injury is 

 noticed. On gooseberry bushes this sprayfluid has proved equally 

 effective. 



PEAR THRIPS. 



Euthrips pyri, Daniel. 



During 1909 this insect appeared in the Evesham district in Plum 

 blossom in large numbers, and to a smaller extent during- 1910. 



It attacks nearly all varieties of deciduous fruits, and is certainly 

 one of the most destructive species of its order. To what extent it 

 is distributed in this country it is difficult to say. The Evesham record 

 is the first for this country, and, curious to say, although countless 

 specimens had been examined in California, the male had never been 

 discovered until found by Mr. R. S. Bag-nail, the well-known authority, 

 amongst some examples I sent him collected at Evesham. 1 



The life-history has been very carefully worked out by Moulton, 2 

 and a summary of his account is here given. 



The egg is bean-shaped (Fig. 6), light-coloured, 

 and almost transparent. 1 1 measures about 0-33 mm. 

 in length. 



After making an incision with the mouth parts, 

 the insect moves forward, lowers and inserts the 

 ovipositor, and by moving the tiny saws she makes 

 a deep incision in the plant tissues. Whilst the 

 FIG. 6. THE PEAR ovipositor is still deeply set in the plant, an egg is 

 conducted through the cavity between the plates 



Eggs. Highly magnified. , , ., , , . , . ^ ni 



(After Moulton) an< ^ deposited beneath the epidermis. 1 he 



ovipositor is then withdrawn, and the egg is left 

 deeply embedded within the plant. 



ijourn. Econ. Biol., 1909, vol. iv, p. 37. 



2 U.S. Dept. Agric., Bur. of Entom., Bull. No. 68, pt. i, 1909. 



