Solitary Bees and Wasps 



needs to be expert in at once keeping her eye on the foe 

 and at the same time delivering an attack from her rear 

 armament. Of course the poor spider is heavily handi- 

 capped by the absence of wings, which enable the wasp 

 to move and make circles round her less agile opponent." 

 The graceful little mud-wasps are often described in 

 natural history books, because of their curiously formed 

 little earthen nests, and the still more extraordinary places 

 in which they build them, such as door-locks, window 

 catches, cotton reels, and the like. An ingenious nesting 

 habit which is rarely mentioned is worth a moment's 

 attention. In each cell the little wasp deposits a single 

 egg and a store of paralysed caterpillars, which, by the 

 way, are usually pushed into their hiding-place by means 

 of the wasp's head. The egg is always suspended by a 

 silken thread to the roof of the cell in such a manner that 

 it hangs just clear of the nearest caterpillar. The wasp 

 grub, when it comes into the world, is very fragile, and 

 might easily be mortally wounded by any movement on 

 the part of its living fare. Therefore, tethered as it were 

 to the silken thread, it makes its first meal out of harm's 

 way, off the nearest caterpillar. But more wonders are 

 yet to come. It is necessary for the wasp larva to reach 

 more food, and it is yet too feeble to venture alone in its 

 larder. The difficulty is overcome in this manner. The 

 egg, from which the larva has emerged, breaks up into 

 a ribbon, thereby lengthening the tether and enabling 

 the hungry little being to reach more of its food supply. 

 With increasing age the young wasp larva gains strength, 

 so that the last of its provisions, in the shape of the 

 caterpillars, are devoured without the aid of the protecting 

 silken thread. 



