DIPLOSIS PYRIVOEA, THE PEAR- GNAT. 123 



It is only necessary for the success of this enterprise, wliich 

 seems to be so univei-sally desired, — for I have received favour- 

 able communications from almost every part of the United 

 Kingdom — that those who desire to be in closer touch with their 

 fellow-workers, should as early as possible enrol their names as 

 country members of the South London Society, the subscription 

 being absolutely nominal in comparison with the advantages 

 received. 



It would be desirable, when sending names for election, to 

 state whether the candidate is willing to act as local Organising 

 Secretar}' in conjunction with the London Secretary ; also tlie 

 particular branch of Biology studied, with reference to at least a 

 couple of known biologists. 



So far as appertains to the Entomological Section of this 

 proposed organisation, the members ma}^ depend upon receiving 

 all possible support and assistance from this Magazine. 



John T. Careington. 

 New Broad Street House, London, E.G., April 22, 1888. 



DIPLOSIS PYRIVOEA, Kiley, THE PEAR-GNAT. 

 Bt R. H. Meade. 



Among the numerous insects which injure our fruits and 

 vegetables, there is a little two-winged fly belonging to the 

 family of Cecidomyiidse, or gall-gnats, which feeds (in the larva 

 state) upon young pears. 



The eggs are laid by the female flies (which possess a very 

 long and slender oviduct) in the interior of the blossom-buds of 

 the pear-tree, before they expand. They are said to dejiosit the 

 eggs upon the anthers of the flower, sometimes piercing tlirougli • 

 the unopened petals to reach them. The eggs soon hatch, and 

 the little maggots bore into the core of the young pear, where 

 they quickly increase in size, and spread and eat in various 

 directions. The vitality of the fruit is not destroyed at once, but 

 it continues to grow ; sometimes becoming, however, distorted 

 and lumpy in shape. By the time these young pears have become 

 an inch or two long the larvie will have attained their full growth, 

 and the fruit has become partly rotten and disorganised in its 



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