CYNIPS. 
265 
the female Cyiiips, which at the same time that 
she deposits her egg, discharges a peculiar fluid, 
which, by preventing the natural course of the 
sap, causes a gradual enlargement to take place. 
Among the most remarkable of these vegetable 
excrescences may be ranked those produced on the 
leaves and footstalks of the Oak; these are well 
known in commerce under the name of Galls of 
Aleppo, the best or most efficacious being import- 
ed from the Turkish dominions. Those on the 
leaves of the oak are produced by the Cyiiips 
Quercus foUi of Linnreus, a small short-bodied fly, 
of a blackish colour, with four transparent wings, 
carried in a flat direction over the back. In the 
month of July this animal punctures the leaves, 
depositing an ovum in each puncture, frequently 
to the number of six, seven, or eight on the same 
leaf In the space of a few days so many small 
round swellings are produced : these towards the 
end of the month arrive at the size of common 
peas, but afterwards increase rapidly, till in the 
month of September they are arrived at the size 
of the largest of those represented on the annexed 
plate: at this period of their growth they are 
generally tinged with red, and marked by minute 
superficial tubercles. On slitting open a gall, the 
larva is found imbedded in the centre, in the form 
of a .small white maggot, not ill resembling that 
of the common nut. In September it undergoes 
its change into chrysalis, in w'hich state it con- 
tinues about three weeks, wdien the complete insect 
