i88 SOLITARY BEES AND WASPS. 



a wasp arrived, each one holding some kind of 

 fly in its mandibles ; as I imagine this went on 

 from early morning till dusk we may easily reply 

 to the frequent inquiry of, What use can wasps be 

 in the world ? and why were such troublesome 

 insects created ? by pointing to the useful labours 

 of this despised creature in reducing, not only the 

 destructive grey caterpillars which abound in our 

 gardens, but also the swarms of flies which beset 

 us in the summer months. 



We had to take down this great fir-tree, as it was 

 completely decayed and likely to fall with the next 

 high wind, and when it was felled we saw the 

 marvellous work the wasps had been carrying on 

 the stem was completely honeycombed with wasp- 

 cells and all through that summer endless numbers 

 of wasps continued to hatch out of the old tree- 

 stem. 



The mason wasps are a very serious evil in 

 Florida and many other hot countries, because of 

 their tendency to fill up every convenient crevice 

 with their mud nests. For instance, a gun may 

 be laid aside for a day or two without a cover, and 

 a mason wasp will at once fill up the barrel with 



