INSECTS INFESTING THE PEAR TREE. 117 



proved to be this species, burrowing into the pith. In 1882, 1 

 received apple, pear, cherry, almond, apricot, peach, and olive 

 branches, all of which were infested by this beetle. I also 

 visited one pear orchard, and one orchard in which olives are 

 grown, and found some trees damaged to a serious extent. 

 The nature of the damage done by this beetle, is the burrow- 

 ing into the branch and eating the center or pith. (Fig. 94, 

 Plate 1.) The place selected to commence operations is gen- 

 erally in the axil of a bud, or small branch. The burrows 

 made are invariably downwards, and measure from six lines 

 to one inch in depth, and from two to three lines in diameter. 

 A pear branch, thirty inches long, contained eleven of these 

 burrows. 



The damage done the trees is caused by their burrows being 

 filled with water by the Winter rains, causing the branches to 

 decay, and also by the branches burrowed breaking off. 



The natural history of this beetle (Fig. 95, Plate 1) has not 

 been fully studied, but it is supposed the eggs are deposited 

 and the larvae live in forest trees. 



The perfect insect, both Inale and female, burrow into the 

 branches of the fruit trees, but the eggs or larvge have not been 

 found in any of the varieties which they infest. This Spring, 

 1883, serious damage has been done by this species to trees 

 planted last year. 



Remedies. — Use No. 27, and early in the Spring spray with 

 Nos. 4, 5, or 7. 



CHAPTER LX. 



The Pear-tree Psylla. (Cal.) 

 (Psylla pyri. — Linnaeus.) 



Order, Hemiptera ; ^ F "1 A 



Sub-order, Homoptera ; ^ ' " ' 



[Living in communities upon and puncturing the twigs of 

 the pear tree; a small, yellowish or greenish louse.] 



These insects possess the power of leaping, and hence in 

 some localities are known by the name of flea-lice. They 



