ANTS, BEES AND WASPS 179 



in the earth, which ramifies into numerous branches, each one 

 ending in a group of cells. The principal gallery, with its single 

 entrance, is common to all ; but the cells are formed and stored 

 by separate individuals. 



The Andrena much resemble the honey-bees, but they are 

 smaller insects. They usually live in colonies, but each bee works 

 entirely alone, and they have no common entrance to their 

 burrows. The tunnels are formed side by side in sandy soil, but 

 a colony will often select a garden path for its excavations. 



The Great Violet Carpenter Bee, Xylocopa violacea, and the 

 Mason Bee, Chalicodoma muraria, are extremely interesting solitary 

 species. The former, which is not uncommon in the south of 

 France, may be known by its velvety black body and violet- 

 coloured wings. It bores into dry wood, forming a shaft a foot 

 or more in depth, giving access to three or four parallel galleries. 

 These galleries are divided into a number of cells with partitions 

 made from the excavated sawdust mixed into a paste with saliva, 

 and in each cell the bee deposits an egg after having provisioned 

 it in the usual manner. The Mason Bee, which is also found in the 

 South of France, builds its nest of earth and gravel, worked up 

 with a secretion of its salivary glands into a kind of cement which 

 sets as hard as stone. Each nest contains eight or nine cells, and 

 a final layer of mortar is plastered over the whole so that it looks 

 like a mass of dried mud about the size and shape of an egg. 



Many species of Osmia, a genus allied to Chalicodoma, are in 

 the habit of making their nests in curious places ; some are fond 

 of clearing out the straws in the thatch on old cottages to form 

 their galleries ; others take possession of empty snail shells, and 

 some have even been known to construct their nests in the lock 

 of a door. 



The Leaf-cutting Bees, Megachile, are often seen at work in the 

 rose garden cutting small neat pieces from the leaves with which 

 to line the interior of their nests. These bees usually avail them- 

 selves of a burrow in the ground made by a worm or an insect, 

 or they may fashion their tunnels for themselves. Their nests 

 are often found, too, in old dry logs and gate-posts. Each little 

 cell, when finished, is about the size and shape of a thimble, the 

 insect deftly fitting the pieces of leaf, one overlapping the other, 

 with her legs and jaws. The thimble-like cell, when completed 



