SOME OTHER BEES 281 



insect of the same order, many of which were, as a matter of fact, 

 busy searching the face of the cUff and entering the burrows. 

 These parasitic bees, scorning the work of constructing bur- 

 rows, deposit their eggs in the nests of the Anthophora as the 

 Apathus does in that of Bombus. It was quite obvious that the 

 projecting tubes, with the entrance beneath, considerably baffled 

 these intruders, who rarely entered a completed tube, but made 

 their way readily into the obvious holes in the cliff. In these, 

 of course, the Anthophora was working, and they contained no 

 provision. Moreover, the attachment of the earth in this 

 manner is a great economy, because, while serving the purpose 

 of a screen, the earth is in the handiest possible place for use 

 when it is needed for making the cell partitions and finally 

 sealing the burrow. 



Visiting the place two days later, I found the bees had 

 disappeared completely, and the cliff bore practically no trace 

 of their operations. 



The procedure of these bees and of the allied genus Osmia, 

 of which several species are found in Britain, is much the same, 

 except for the construction of the tube, which is apparently 

 confined to this species. Otherwise, all make a tunnel into the 

 cliff or wall, which does not, however, run directly at right 

 angles, but, after entering a little way, turns sharply, so that 

 the cubicles of the larvae lie parallel with the cliff face. A mass 

 of pollen and honey having been deposited at the end of the 

 burrow, grains of earth are formed into a partition to divide the 

 cells, in each of which one egg is deposited with an adequate 

 supply of food. Finally, the burrow is filled up and the larvse 

 left to undergo their transformations in safety. One species 

 of Osmia, which in sandy districts builds in this manner, selects 

 old posts or soft -wooded trees such as willow when living in an 

 argillaceous neighbourhood, and thus forms an interesting link 

 between the Mason-bees and Carpenter-bees, Xylocopa, whose 

 work is of an exceedingly interesting character. 



V 



Most of the Carpenter-bees are tropical species of consider- 

 able size and beauty, but one or two are found in Europe, quite 

 plentifully, in fact, in the South and East. The Violet Carpen- 

 ter-bee is a very handsome insect, as large as a Bumble-bee and of 

 somewhat similar build, but only slightly hairy, its body and 

 wings being of rich metallic blue, with a violet tinge. The 

 jaws of this bee are exceptionally well developed, and it fre- 

 quently makes its tunnels into hard new wood, the timbers of 

 house-roofs being favourite places. Like the other solitary 

 bees, the female makes her burrow angular, the bulk of it lying 



