ROSE-GALLS. III 
The Cynips Kollari is larger than the generality of the 
family, equalling a small house-fly in dimensions. Its 
colour .is pale brown. A figure of the insect may be 
seen in the illustration. 
Nearly in the centre of the illustration is seen a figure 
of the well-known gall that is so common on the rose, 
whether wild or cultivated, and which is popularly known 
by the name of BreprGuar. ‘This gall is caused by a 
very tiny and very brilliantly-coloured insect, named 
Cynips rose, which selects the tender twigs of roses, 
and deposits its eggs upon them. 
I have now before me quite a collection of these galls, 
some of which are so variable in shape that they scarcely 
seem to have been made by the same species of insect. 
When the Cynips rose deposits her eggs upon the rose, 
the effects are rather remarkable. Each egg becomes 
surrounded with its own cell or gall, and the whole of 
them become fused into one mass. The exterior of these 
galls is not smooth, like that of the specimens which have 
been described, but is covered with long, many-branched 
hairs, which stand out so thickly that they entirely con- 
ceal the form of the gall itself. 
-Reaumur, who gave much attention to galls, thought 
that the hairs were formed by the exudation of sap 
through little orifices in the growing gall, just as the web 
of the spider is formed by the exudation of a glutinous 
liquid from minute pores. This theory, however, is 
scarcely tenable, because sap has no power of hardening 
into threads when exposed to the air, and, besides, a 
well-defined vegetable structure is seen in the hairs, 
which would not be the case if they were merely har- 
dened sap. Moreover, if the hairs were formed in this 
manner, they could not have the power of throwing out 
