HYMENOPTERA. 



667 



than the mentum (Fig. 795) ; the basal segments of the 

 labial palpi are also elongate. 



A remarkable difference in habits exists 

 among the different species of this family : 

 some are solitary; others are inquilines ; 

 and a few are social. Among the solitary 

 species we find an even greater variation in 

 the form of the nest than we found among 

 the solitary wasps or among the digger- 

 wasps. Some of these bees are miners, 

 digging tunnels in the ground ; some are 

 masons, making their nests out of mortar- 

 like mud ; some are carpenters, boring 

 tunnels in the pith of plants or in solid 

 wood ; and some are leaf-cutters, lining 

 their nests with pieces of leaves or of petals 

 of flowers. We have space to describe the 

 habits of only a few of these. 



I. THE SOLITARY LONG-TONGUED BEES. Fig. 7 o 5 .-Labium of 



the Honey-bee: s, 



The Leaf-cutter Bees, Megachile (Meg- tumTTpaipusT^ 

 a-chi'le). — The bees of the genus Megachile e lossa - 

 have the curious habit of making cells for their young out 

 of neatly-cut pieces of leaves. These cells are packed away 

 in such secure places that one does not often find them ; 

 but it is a very easy thing to find fragments of leaves from 

 which the pieces have been cut by bees. The leaves of 

 various plants are used for this purpose, but rose-leaves are 

 used more frequently than any other kind. In Figure 

 796 there are represented one of these bees, its nest, and 

 a spray of rose-leaves from which pieces have been cut by 

 the bee. 



The species represented here, Megachile acuta (M. a-cu'ta), 

 is a carpenter as well as a leaf-cutter. It first makes a tun- 

 nel in wood, often selecting that which is partially decayed ; 

 then it proceeds to build a thimble-shaped tube at the hot- 



