HYMENOPTERA. 399 



the oak-tree (Cynips quercusfolii), 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 



Fig. 375.-Gall insect Fig. 376. Oak Galls, produced by Fig. 377. Interior 



(Cynips quercusfolii). Cynips quercusfolii. of a Gall. 



used in the manufacture of ink, is the produce of a foreign Cynips, 

 which lives on an oak found in the East. Apples of Sodom, which 

 travellers bring back from the shores of the Dead Sea, are large 

 galls,* full of dust and dry larvae. 



The Urocerata and the Tentkredinetae 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, 

 without any pedicle. 



The insects of the genus Sirex (Fig. 378), belonging to the former 

 of these, lay their eggs in living wood, and their larvae 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 (Sirex gigas] possesses a long recti- 

 linear auger. The mandibles of the larvae 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 Academie 

 des Sciences some packets of cartridges containing balls which had 



* Made by Cynips insana. ED. 



