204 NATURES STORY OF THE YEAR 



when needed. Each cell is made slightly larger 

 than the builder. The walls are raised very 

 slowly, each successive lump of mortar being 

 patted and worked into the exactly appropriate 

 position. And viewing this exercise of care and 

 skill, these little pats and caresses of the pliant 

 mortar, and the artificer's frequent surveys of the 

 whole work, one is reminded of human fore- 

 thought, human patience and skill. There is 

 more than instinct in it ; there are the perception 

 and ingenuity that can discover and strengthen 

 .the weak places in the walls, and remedy acci- 

 dents as they occur. A whole day often passes 

 in the making of a single cell, and if this be 

 completed before evening, the wasp sleeps in it 

 with her head towards the opening, ready to 

 defend it against all intruders. A cell having 

 been completed and finally critically surveyed, 

 the wasp proceeds to fill it with the small green 

 larvae or grubs which are so plentiful on fruit 

 trees and common bushes. They are stung 

 sufficiently to be paralysed but not killed, and are 

 thrust helpless into the cell. When this is filled, 

 an egg is laid among the grubs, and the chamber 



