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but for this precaution the eggs would fall out. 

 These soon hatch, but the minute grub does not 

 cast off the whole of the egg-shell : it keeps the 

 hinder portion of its body in the base of the egg- 

 shell until its final cast of skin, and by this means 

 retains its hold of the cell. 



Until the eggs hatch the mother wasp is free to 

 extend her home. She builds a paper umbrella 

 over her three-celled comb ; she adds other cells 

 to the first three ; she encloses the comb in a pear- 

 shaped bag with an entrance at the narrow lower 

 end. When the eggs are hatched two or three 

 days later she has to provide the grubs with food 

 continuously, and she does this by capturing flies 

 and other insects, masticating the soft parts and 

 feeding the grubs from mouth to mouth, much as 

 a bird feeds her callow nestlings. With such care 

 and attention the grubs grow rapidly, and in 

 between her food-finding excursions she has to 

 find time to visit the fence, to get more wood 

 raspings with which to increase the depth of the 

 cells. If you look at a piece of wasp-comb you 

 can trace the growth of the cell-wall by the lines 

 of slightly varying colour. 



When the grub has reached its full dimensions 

 it spins a silken cap over the mouth of the cell, 

 and continues the silken layer down to the bottom 

 of its cell. This is its cocoon. The upper part 

 is of the same close texture as the cap, but lower 

 down it becomes much thinner. In this cocoon 

 the grub changes to a chrysalis, and after a rest of 



