The Tribulations of the Mason-bee 



The stealers of food are the Stelis-wasp 

 {Stelis nasuta) and the Dioxys-bee {Dioxys 

 cincta). I have already said how, in the 

 Mason's absence, the Stelis perforates the 

 dome of cell after cell, lays her eggs there and 

 afterward repairs the breach with a mortar 

 made of red earth, which at once betrays the 

 parasite's presence to a watchful eye. The 

 Stelis, who is much smaller than the Chalico- 

 doma, finds enough food in a single cell for 

 the rearing of several of her grubs. The 

 mother lays a number of eggs, which I have 

 seen vary between the extremes of two and 

 twelve, on the surface, next to the Mason's 

 egg, which itself undergoes no outrage what- 

 ever. 



Things do not go so badly at first. The 

 feasters swim — it is the only word — in the 

 midst of plenty; they eat and digest like 

 brothers. Presently times become hard for 

 the hostess' son: the food decreases, dearth 

 sets in; and at last not an atom remains, al- 

 though the Mason's larva has attained at 

 most a quarter of its growth. The others, 

 more expeditious feeders, have exhausted the 

 victuals long before the victim has finished 

 his normal repast. The swindled grub 

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