262 



ELEMENTARY ENTOMOLOGY 



the largest species of the order, being nearly two inches long 

 and having a wing expanse of over three inches. Not infrequently 

 it is overpowered and destroyed by its formidable prey. 



FIG. 416. The tarantula-killer (Pepsis formosa}. (Natural size) 



The thread-waisted wasps (Sphecidae) are readily recognized by 

 the very long, threadlike petiole of the abdomen, and include our 

 common mud-daubers, which make their nests under the eaves of 



buildings and in barns, attics, etc. 



The nests are composed of sev- 

 ;^v eral tubes placed side by side, 

 each of which is provisioned 

 with spiders. They may be seen 

 around pools, collecting mud for 

 their nests, and jerking their 

 wings from side to side in a 

 nervous manner. 



A nearly related family (Bern- 

 be cidae], which burrows in the 



FIG. 417- A mud-dauber (FOopaeu* sand and provisions its nests with 



cementarius] flies and similar insects, includes 



(After s. j. Hunter) the large cicada-killer. This is 



