THE MUD-DAUBERS. 187 



fall far below some of those that are found in other parts of the 

 world. Monteiro, in his work, "Angola and the Eiver Congo" 

 (p. 323), says that he has opened many of the nests of Pelopaeus 

 spirifeco and has always found the spiders alive, though unable 

 to crawl away when taken out. "Whilst at Bembe," he says, 

 "I fortunately witnessed a fight between a large specimen of 

 these wasps and a powerful spider which had built its fine web 

 'on my ofiice wall. The spider nearly had the wasp enveloped 

 in its web several times, and by means of its long legs prevented 

 the wasp from reaching its body with its sting, but at last,: after 

 a few minutes' hard fighting, the wasp managed to stab the 

 spider right in the abdomen, when it instantly curled up its 

 legs and dropped like dead to the ground. The wasp pounced 

 down on it, but I interfered, and picking up the spider placed it 

 under a timibler to ascertain how long it would live. * * * 

 It lived for a week, and, although moving its legs when touched, 

 had no power of locomotion, showing that the poison of the 

 wasp has a strong paralyzing effect." Eversmann gives similar 

 testimony in regard to Pelopaeus distillarins. He has opened 

 forty cells of this species and has always found the spiders alive.* 

 Thus we have, in the different species of this genus, the widest 

 variation in the habit of stinging the prey. Some kill almost 

 all of the spiders, others kill more than half, while yet others, it 

 is claimed, put up all their victims in a living but helpless con- 

 dition. 



Our wasps did not share the habit of those observed in France, 

 in laying the egg upon the first spider placed in the cell. In- 

 deed we found that it was only after the nest was completely 

 provisioned that the egg was laid, on the abdomen of one of 

 the last spiders brought in. The importance which Fabre at- 

 taches to the early laying of the egg seems to us a little exagger- 

 ated as the difference in time in the two methods of procedure 

 cannot be enough to give much advantage either way. We 

 have often counted the number of journeys that a wasp makes 

 in an hour, and have found that it averages from twelve to 

 *Bulletin Mosc, Tome XXL, 2, 1848, p. 248. 



