The Tribulations of the Mason-bee 



move the obscurity of the next. I can see 

 nothing to account for the absence or at least 

 the extreme rareness of usurpers of provisions 

 and consumers of grubs, both of whom are 

 very Indifferent to the new or old conditions 

 of the nest, so long as the cells are well 

 stocked. Can It be that the lofty position of 

 the edifice and the shaky support of the 

 branch arouse distrust In the DIoxys and 

 other malefactors? In the absence of a bet- 

 ter explanation, I am needs content to leave 

 It at that. 



If my Idea is not an empty fancy, we must 

 admit that the Challcodoma of the Shrubs 

 was singularly well-Inspired In building in 

 mid-air. You have seen of what misfortunes 

 the other two are victims. If I take a census 

 of the population of a tile, many a time I find 

 the DIoxys and the Mason-bee in almost 

 equal proportions. The parasite has wiped 

 out half the colony. To complete the disas- 

 ter, It Is not unusual for the grub-eaters, the 

 Leucospis and her rival, the pygmy Chalcldid, 

 to have decimated the other half. I say no- 

 thing of Anthrax sinuata, whom I sometimes 

 see coming from the nests of the Challco- 

 doma of the Sheds; her larva preys on the 

 27s 



