WASPS. 183 



(if any) in the lives of our wasps with those of other 

 lands. Peckham noted that two-thirds of the spi- 

 ders are killed at capture, most died in a week, and 

 a few lived for nearly six weeks. He noted that 

 the Qgg was laid almost invariably on the last spider, 

 while Fabre records the egg being placed on the first 

 captured spider. 



Sometimes one finds an empty cell, or a cell packed 

 with food store and no egg has been laid in it. 



These wasps are often attacked by parasites. 

 From a very large nest we bred out parasitic Tach- 

 inid flies, and one of the parasitic wasps. 



In building the mud nest the mother wasp has a 

 very bugy time. As many as 40 to 50 loads of mud 

 are carried in its mouth to form just one cell. The 

 following are notes made from observations of a 

 "pin waisted" wasp. 



Notes on Pelopaeus laetus. 



ii 



J A ]:)retty yellow and black mud wasp {Pelo- 

 paeus laetus) flew^ into the room and apparently be- 

 gan looking for a spot to build its nest. iMually 

 the corner of the ceiling vs'as selected in 

 preference to many sites previously inspected. The 

 wasp crawded over the surface several times, and 

 appeared to be scratching it. This action may 

 possibly have been to roughen the surface so that 

 the mud would adhere more readily. The builder 

 now flew away, but shortly returned with a rounded 

 pellet of mud in its jaws. This was placed on the 

 selected spot, and the front feet appeared to flatten 

 it out to make it cover the greatest space. Many 



