PEAR LEAF-BLISTEE MITES. 87 



turning browner. " (? Tijplilodromm pijrl, Scbeuten ; ? Phi/toptus 



pyri, Pagenstecker.)''' 



This Pear-leaf infestation is not often enquired about, but per- 

 sonally, for at least about sixteen years or more, I have never needed 

 specimens without being able to find them in my own garden, and 

 probably if attention was directed to the nature of the attack, a good 

 deal of damage, of which the cause is not suspected, might be spared. 



In the course of last year I had enquiries about this attack from 

 various correspondents, but as these did not add to our information on 

 the subject it is unnecessary to give them here. 



Under various synonyms the infestation is widespread, both in 

 the Old and New World ; and the following notes, from the very 

 trust wortby hand of Mr. James Fletcher, Dominion Entomologist, 

 Ottawa, Canada, recently published, appear to me to embody in 

 serviceable form almost all that we need to know of its history. 



" Pear-leaf Blister Mite, Fhytoptus pi'P'^" An insect which is 

 giving a considerable amount of trouble in Canada at the present time 

 is the Pear-leaf Blister Mite." . . . . " The mites, which are hardly 

 visible with the naked eye, emerge from the scales of the leaf-buds 

 early in spring, and attack tbe tissues of the unfolding leaves. The 

 blisters soon begin to show as small red spots, each of which has a 

 small central hole on the lower side of the leaf. The eggs are laid 

 inside these blisters, and the young, escaping through the central 

 opening, at once form new galls, until sometimes the greater part of 

 most of the leaves is rendered unfit to perforin its functions. 



"When mature the galls are brown and spongy in texture, and 

 are raised perceptibly above the surface of the leaf. Before the 

 leaves fall the mites leave the galls, and secrete themselves beneath 

 the scales of the winter buds, where they remain throughout the 

 winter. 



"As a remedy, kerosine emulsion seems to be the only substance 

 which, up to the present time, has given any promising results." — 

 From " Keport of the Ontario Fruit Grrower's Association," p. 113, 

 published in the ' Annual Eeport of the Department of Agriculture of 

 Ontario for 1892.' 



For those who do not care to be at the trouble of mixing the 

 emulsion themselves, the very similar mixture sold in this country, 

 under the name of " antipest," and especially referred to in the 

 preceding paper on Gooseberry Ked Spider, p. 37, would be found to 

 have very nearly (or precisely) the same eflects. 



* Nalepa, 'Zur system der Gallmilben,' Sitzgsbers, 1890, pp. [50, 51] 11, 12; 

 plate iv., figs. 1, 2. See also references iu ' Katalog. der bislier beschrieben Gall- 

 milben,' by Dr. Nalepa, pp. 275 and 2'J6. 



