398 THE INSECT WORLD, 
(Cynips quercusfolit), and Figs. 376 and 377 the galls it produces. 
The galls of the rose are hairy, and are sometimes called “ Robin’s 
Cushion.”’ The gall-nut, rich in tannin, which is used in the 
a 






Firat Ws 
iat 
. ial Wr 
a 
it 
i 
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Fig. 375.—Gall insect Fig. 876.—Oak Galls, produced by . Fig. 377.—Interior 
(Cynips quercusfolit). Cynips quercusfolit. of a Gall. 
manufacture of ink, is the produce of a foreign Cynips, which lives 
on an oak found in the Kast. Apples of Sodom, which travellers 
bring back from the shores of the Dead Sea, are large galls,* full 
of dry dust and larvee. 
The Urocerata and the Tenthredinete form two tribes of insects, 
of which the first are of great size, have a cylindrical body, the 
abdomen being attached to the thorax in its whole breadth, with- 
out any pedicle. 
The insects of the genus Szrex (Fig. 378), belonging to the 
former of these, lay their eggs in living wood, and their larve live 
for many years in the interior. They are to be met with in great 
numbers in forests of pine trees, and according to Latreille, show 
themselves sometimes in such great numbers as to become an object 
of terror. The female of the Giant Sirex (Szrex gigas) possesses 
a long rectilinear auger. The mandibles of the larve are of great 
strength, and are even capable of perforating lead. This fact has 
been observed many times. In 1857 Marshal Vaillant presented 
to the Académie des Sciences some packets of cartridges containing 
* Made by Cynips insana,—Ep. 
