6 i6 
THE STUDY OF INSECTS. 
that not all of the members of this family are developed 
in galls, and that galls are produced by many insects 
that do not belong to this family. Galls made by mites, 
plant-lice, flies, and moths have been described in the pre^ 
ceding pages, and galls are also produced by beetles and cer¬ 
tain other insects; but the great majority of these strange 
growths are made either by mites, plant-lice, or true gall¬ 
flies (Cynipidae). 
The galls made by mites and plant-lice have open mouths, 
from which the young of the original dweller escape. But 
in the case of the gall-flies the gall is closed,and a hole must 
be made by the insect in order to emerge. Moreover, there 
is no reproduction of insects within the galls of gall-flies, as 
there is within the galls of mites and plant-lice. Many 
species of gall-flies undergo their transformations within 
their galls; while in other species the full-grown larva leaves 
the gall and enters the earth to transform. But in each case 
the adult female provides for the production of new galls, 
in which their young are to develop. 
In the adult gall-fly the abdomen is usually much com, 
pressed. It is joined to the thorax by a short peduncle, the 
first abdominal segment (Fig. 
745). The second and third 
abdominal segments are large, 
and the remaining segments, 
usually five in number, are 
short, and eacli is more or less 
covered by the preceding seg¬ 
ment. Concealed within these 
segments is the long, partially 
coiled, very slender ovipositor, 
Fig. 745* Amphiboiips spo 7 tgi/ua. which arises near the base of 
the abdomen. The wings of gall-flies have compara¬ 
tively few veins, and the fore wings lack the stigma ; some 
forms are wingless. The antennae are not elbowed, and 
consist of from thirteen to sixteen segments. The larvae 
