Insects. 583 



process of building ; and thus of setting at rest, to my own satisfac- 

 tion, the disputed point of ownership to these nests, which some en- 

 tomologists have attributed to Eumenes, supposing the Pelopaius to 

 be parasitical. The following observations will show that sometimes, 

 at least, the latter builds. I transcribe now from my journal. 



June 30. — I w> atched with much interest the proceedings of a 

 dauber, in building her mud cells : it is a pretty species, Pelopaeus 

 flavipes. She has chosen the ceiling of a cupboard in my sitting- 

 room, w r here, previously to my observing her, she had made one cell, 

 and half another parallel to it ; the former w T as closed, the latter had 

 got its contents of spiders, and only wanted closing. Such was the 

 statu quo. I had not seen the dauber go in for some time, so that 

 when she did go in, I watched her from her recommencement. She 

 came empty, and having for some moments peeped in, and examined 

 the contents to see that all was right, she suddenly flew out at the 

 door (which as well as the window was almost constantly open), and 

 returned in about a minute with a lump of soft wet mud in her jaws, 

 about twice as large as her head. Where she got it in so short a 

 time I don't know ; it was perfectly kneaded, and free from all lumps, 

 or grit, and was worked, when laid on, as freely as butter. I suspect 

 that it was formed of dry dust, on which she had poured a drop of 

 fluid from her mouth. She laid the substance on the open end of the 

 unfinished cell, and spread it about with her jaws very expeditiously 

 and skilfully, till the orifice w r as quite closed up. She then flew off, 

 and returned with a similar load, w T hich she applied upon the last to 

 make it thicker. When she was gone the third time, to observe her 

 behaviour, I thrust the head of a pin through the newly laid mortar, 

 opening a hole into the cell. On her return, she at once perceived 

 the hole, and deposited her lump upon it, spreading it about as before. 

 I played her the same trick several times, at all of w T hich her proceed- 

 ings w r ere the same, save that at length she seemed to become very 

 angry, and endeavoured to catch the house-flies that were flying and 

 crawling near. I have no doubt that she suspected them of having a 

 hand in it. At all events, she jumped at them very snappishly when- 

 ever they came near, and sometimes even with the load in her mouth, 

 but I did not see that she caught one. Once too, a large Ichneumon 

 was lurking about, at whom she fiercely flew, and I think they had a 

 short struggle. At times she would linger at a little distance after de- 

 positing her load, apparently hoping to catch the insidious house- 

 breaker, " in the manner," as lawyers say. 



At length I broke off a large piece from the side and bottom, ex- 



