OF NATURAL HISTORY. 329 



proteiSt her progeny from enemies of every kind, one ftiould natu- 

 rally imagine that the young worms were in perfedt fafety, and that 

 their caftle was impregnable. But, notwithftanding all thefe favou- 

 rable precautions, the young of the mafon-bee are often devoured 

 by the inftindtive dexterity of certain fpecies of four-winged infefls, 

 diftinguifhed by the name of ichneumon flies. Thefe flies, when the 

 mafon-bee has nearly completed a cell, and filled it with provifions, 

 depofit their own eggs in her cell. After the eggs of the ichneu- 

 mon flies are hatched, their worms devour not only the provifions 

 laid up by the mafon-bee, but even her progeny whom fhe had la- 

 boured fo hard, and with fo much art and ingenuity, to protect. 

 But the mafon-bee has an enemy ftill more formidable. A certain 

 fly employs the fame ftratagem of infinuating an egg into one of 

 her cells before it is completed. From this egg proceeds a ftrong 

 and rapacious worm, armed with prodigious fangs. The devafta- 

 tions of this worm are not confined to one cell. He often pierces 

 through each cell in the neft, and fucceflfively devours both the 

 mafon-worms, and the provifions fo anxioufly laid up for their fup- 

 port by the mother. This ftranger worm is afterwards transformed 

 into a fine beetle, who is enabled to pierce the neft, and to make 

 his efcape. 



The operations of another fpecies of folitary bees, called ivood- 

 piercers, merit attention. Thefe bees are larger than the queens of 

 the honey-bee. Their bodies are fmooth, except the fides, which 

 are covered with hair. In the fpring, they frequent gardens, and 

 fearch for rotten, or at leaft dead wood, in order to make an habi- 

 tation for their young. When a female of this fpecies, for flie re- 

 ceives no afTiftance from the male, has feleded a piece of wood, or 

 a decayed tree, fhe commences her labour by making a hole in it, 

 which is generally direded toward the axis of the tree. When flie 

 has advanced about half an inch, fhe alters the diredion of the hole, 

 t T t and 



