tiVMENOPTERA. 



39S 



have a sickle-shaped abdomen. They lay their eggs on the skin 

 of caterpillars, which they attack with the short cutting auger with 

 which they are provided. 



The Cynips, or Gall-insects, are small black or tawny Hymen- 

 optera, the females of which have an auger, rolled up spirally and 

 hidden in a fissure of the abdomen, with which they prick the young 

 shoots of plants. A peculiar liquid which they pour into the hole 

 round the egg they have laid, causes an excrescence to grow, which 

 is called a " gall." The larva is developed in the centre of this gall, 



Fig. 375. — Gall insect 

 {Cynips qnerciisfolit). 



Fig. 376. — Oak Galls, produced by 

 Cyiiips qnercusfolii. 



Fig. 377. — Interior 

 of a Gall. 



and transformed into a pupa, and afterwards into a perfect insect, 

 which makes its exit by a hole in the wall of its prison. Fig. 375 

 represents the Cynips of the oak tree {Cynips qnercusfolii)^ 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 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 dry dust and larv?e. 



The Urocerata and the Tenthredinetce form two tribes of insects, 



* Made by Cynips insana. — Ed. 



