WASPS AND BEES. 43 



Many Hymeiioptera live upon plants. Of -these some saw 

 holes in the leaves and deposit their eggs in them ; the eggs 

 produce larvae resembling caterpillars, which feed upon the 

 leaves; and the insects are consequently called "leaf-wasps" 

 and " saw-flies/'' Others, called "wood-wasps" and "tailed 

 wasps," bore into trees and provide for their tender offspring in 

 the interior of the stems ; whilst others, with proverbial industry, 

 collect the nectar and pollen of flowers, and with these substances 

 nourish their young, often living together in great societies in 

 most ingeniously constructed dwellings. 



But all are not contented thus to seek their food. Many of 

 them live by rapine and murder. Sand- wasps (Sphegidae) dig 

 holes in the earth, and into these drag their victims to serve as 

 food for their young ; others, such as the Ichneumonidse, too 

 lazy to make such a provision for their progeny, attack other 

 insects, especially caterpillars and larvae, pierce them and deposit 

 eggs in their bodies ; and the larvae developed from these eggs 

 devour their victim whilst still living. The last may be called 

 Entomophaga. All these conditions were realized in Miocene 

 times ; for among the eighty species of Hymenoptera found at 

 (Eningen we may recognize Tenthredinidae, Entomophaga, 

 Sand-wasps, Ants, and Bees, all of which doubtless followed the 

 same modes of life as their existing descendants. 



The Bees furnish fourteen species. A wood-bee (Xylocopa 

 senilis, fig. 295) is found which was probably of a fine blue colour, 

 and constructed perpendicular canals in old trunks of trees, in 

 which to provide for its young. Three Osmice, three species of 

 humble-bees, and five Anthopharites probably made their nests 

 on sunny banks, where they fed their young with honey and 

 pollen. A large humble-bee (Bombus Jurinei, Heer) is repre- 

 sented in fig. 296. A honey-bee (Apis adamitica, Heer, fig. 287) 

 also, even at that early period, hummed about the flowers, and 

 no doubt lived in large societies, built waxen combs, and col- 

 lected honey ; for it is so like the living species (Apis mellifica, 

 Linn.) that it must probably be regarded as the ancestor of that 

 species. 



Of the Wasp family (Vesparia) one species (Polistes primitiva, 

 Heer) belongs to a genus the species of which only construct 

 small nests suspended from plants or attached to rocks and 



