Mason-Wasps. 



35 



its young, and presently returns, bearing with her a grub, 

 which she clasps tightly under her chest, so that her wings 

 may be at liberty. She then takes the grub to the bottom of 

 the tunnel, deposits an egg upon it, and if the grub be a 

 small one, goes off to fetch another. When a sufficiency of 

 food has been obtained, she covers up the grub and egg and 



leaves the latter to its fate. In due time it is hatched, and 

 begins straightway to feed upon its unfortunate fellow- 

 prisoner. When all the food is gone, it is old enough to 

 assume the perfect form, and when it finally becomes a per- 

 fect insect, it makes its way into the open air, and straightway 

 looks out for a mate. 



An European species of this genus, which is called Scdia 

 flavifrons, is remarkable for the four large, round spots on 

 the upper surface of the abdomen. This species always feeds 

 its young on the grub of a beetle, one of the lamellicorn 

 group, and in this case the grub is so large that one is sufficient. 



