162 HOMES WITHOUT HANDS. 



Now, however, a change takes place. The cells of which the 

 next few terraces are composed are of very much larger dimen- 

 sions than the others, and are intended for the purpose of hatch- 

 ing the grubs which will afterward become perfect male and 

 female wasps. It will be seen, therefore, that the workers are 

 hatched in the earlier part of the year, and that the male and fe- 

 male do not make their appearance until the end of the season. 

 The cell-terraces increase gradually in diameter until the fourth 

 or fifth, when they usually decrease slightly, and in exact accord- 

 ance with their enlargement the covering is extended over them. 

 A large nest will contain about seven or eight thousand cells; 

 and, on the average, each cell is the birth-place of three genera- 

 tions. As all the young grubs have to be fed with animal sub- 

 stances, usually flies, the reader can easily imagine the havoc 

 which Wasps make in the insect world. Mr. F. Smith, however, 

 who has given so much time and labor to this subject, remarks 

 that as he has never found the cells of the males and females to 

 contain the remains of more than one lining, these cells only ac- 

 commodate a single brood. 



The silken cover is always convex, and draws the mouth of the 

 cell into a rounded form, so that if one of the cells is removed 

 from the comb while the pupa is still within it, the two ends are 

 of very similar form. The Wasps do not break through the cover 

 in the same manner. Sometimes they burst their way through 

 the centre, leaving a rude and rugged opening ; sometimes they 

 bite out a circular hole, and push their way through it, tearing 

 the edges as they pass through its substance ; and sometimes they 

 cut it neatly round the edge, so that the entire covering can be 

 lifted like the lid of an ancient tankard, and the imprisoned in- 

 sect is able to emerge without any trouble, the lid closing again 

 as soon as the inmate has escaped. 



The covers of the cells are not precisely perpendicular, but radi- 

 ate slightly from the centre of each comb or terrace. Nor is the 

 flooring precisely flat, for the edges of each comb are slightly 

 raised, so as to form a trifling concavity in the centre. At their 

 mouths, the cells are perfectly hexagonal — those, at all events, 

 which occupy the centre of each comb ; but their bases are always 

 cup-shaped, the walls changing gradually into hexagons as the 

 cells increase in height, or, to be more accurate, in depth. When 

 viewed from above, tbe forms of the bases are plainly perceptible, 

 and they look very like the mosaic teeth in a skate's jaw. 



