INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



THE PEAR-LEAF BLISTER-MITE 



Eriophyes pyri (Pagenstecher) (Family Eriophyidse) 



{Phytoptus pyri Pagenstecher) 



(Figs. 5, 8) 



Description.— The work of this mite makes its presence easily dis- 

 tinguishable from all others. Pear leaves are so affected as to produce 

 reddish or dark 

 brown spots which 

 become darker with 

 age and may spread 

 so as to entirely cover 

 and destroy the fol- 

 iage. On the apple 

 the galls remain the 

 color of the leaves. 

 The younger shoots 

 suffer most. The 

 mites are very min- 

 ute and can be seen 

 only with the aid of 

 a microscope. The 

 body is elongated, 

 transversely ribbed, 

 transparent and has 

 but two pairs of legs 

 near the head. 



Life History.— The 



mites j)ass the winter 

 on the trees under 

 the bud scales and 

 begin to work upon 

 the leaves just as 

 soon as the buds 

 begin to open in Feb- 

 ruary. Tbe eggs are 

 deposited in the tis- 

 sues of the leaves, 

 and the feeding of 

 the young causes the 

 small characteristic 

 swellings so often 

 seen upon the foliage. 

 Their work continues 

 throughout the sum- 

 mer, there being Sev- Fig 5._work of the pear-leaf blister-mite, Erio- 

 e r a 1 generations a phyes pyri (Pgst. ), on fruit and leaves of pear. The 



picture of the fruit is slightly enlarged and that of 

 year. the leaves reduced. (Original) 



