$35 On two Species of the Sphex or IVasp, 



In the inside of a house the wasp finds no place, so con- 

 venient to build its nest as the back of a picture, because it 

 prefers establishing i:, : elf in places where" there is nut too 

 much light ; and the back of a picture has also the advan- 

 tage of furnishing two walls to its ceil. The hollow mould- 

 ings in a pannel retain if strongly, as well as the interior 

 angles of a table. In the wooden houses of Virginia, 

 such places swarm with their nests. 



I have seen the empty space between the top of the books 

 and the upper shelf of a bookcase occupied by a whole familv 

 of these wasps, which had saved themselves a great deal of 

 trouble in this instance, as thev had only to build one divi- 

 sion in their nests. 



The nests of the Pennsylvanian wasps differ essentially 

 from those of the sphex ccert/lea. In place of Jong tube? 

 divided into distinct cells, the former construct horizontal 

 chambers contiguous to each other. They are completely 

 polished within, but are more coarsely wrought without. 



Both species of these insects, however, prepare the same 

 Jund of food for their young ; that is to say, spiders of every 

 kind, but especially those which do not secure themselves 

 by very extensive webs. It is a kind of yellow spider which 

 the wasp collects in greatest quantities. The author, how- 

 ever, has seen both species attack very large spiders in the 

 middle of their webs, and surrounded with the carcases of the 

 insects they had devoured ; he has even seen one of these wasps 

 dart quickly upon the spider and wound it with its sting. 

 The wasp then retired to clean itself from some fibres of the 

 web; which it did like the common fly, by brushing its 

 wings and head with its legs. After having been at- 

 tacked several times, the spider tried to effect its escape by 

 dropping quickly down by means of its thread to the floor, 

 when it began to run off; but its antagonist continued to 

 sting it, and even attempted to carry it off: the spider was, 

 however, too large and heavy ; and although the wasp tried 

 to lighten the weight by cutting off the spider's less, it did 

 not succeed in carrying off its booty for a whole hour, during 

 which time the author was watching. 



The 



