TRACHEATA 379 
The pupae he in a cocoon which is found in the neighbour- 
hood of their food plant, often on the ground. <Athalia spinarum 
is the turnip saw-fly; and Lophyrus pini causes much damage 
to young Scotch firs. 
Sub-order 2. Entomophaga. 
CHARACTERISTICS.— The abdomen is pedunculated. A well de- 
veloped ovipositor is present in the female. The larvae are 
usually parasitic in the larvae of other insects, sometimes in 
plants ; they are apodal and aproctous. 
Family CynipiparE (Gall-flies)—Small Hymenoptera with 
a much-compressed abdomen, the first and second segments of 
which are large, the others very short. There is a long coiled 
ovipositor which arises near the base of the abdomen, and is 
only fully extended when in use. ‘The ova are large, and are 
said to increase in size during developement. The larvae are 
short white fleshy apodal grubs, which feed on the galls in 
which they live. The pupae may be in the gall or under 
eround. Some are parasitic in Diptera and Aphides. 
The oak-apple is formed by a member of this family, 
Andricus terminalis; the common spherical woody galls in 
the oak, by Cynips kollari; and the “spangle galls” in the 
leaves of the same tree by Newroterus lenticularis. Rhodites 
vosae, another member of this family, gives rise to the beauti- 
ful moss or bedeguar galls on rose-trees. 
Family IcHNEUMONIDAE (Ichneumons).—Insects with long 
Fic. 213. 
Aphideus avenae, to the 
left. 
si Ephedrus plagiator, to the 
right. 
slender bodies, with an exserted, often very long ovipositor. 
The abdomen has seven segments. The antennae are 
