INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



Fig. 6. — The pear-leaf blister-mite. Eriophyes pyri (Pgst.). Side 

 view, greatly enlarged. (After Nalepa from Parrott) 



Nature of Work. — The work of this mite is exceedingly character- 

 istic and may be recognized at once by the illustration in Fig. 5. Small 

 light green and reddish swellings or galls are first produced upon the 

 leaves. These later turn black. Upon the fruit small, nearly circular 

 marks of yellow, red or brown are produced, resembling a slight attack 

 of scab. The work upon the fruit is usually done before it is one third 



Fig. 7. — Apple leaf showing the work of the pear-leaf blister-mite, 

 Eriophyes pyri (Pgst). Enlarged twice. (Original) 



grown, but the marks may grow with the fruit and injure it for 

 market purposes other than for drying and canning. Upon young 

 trees much damage is sometimes done, as the tender shoots are often 

 stunted by the mites. On the foliage of the pear the galls are usually 



