Dec, I902.] Banks: Si.kki'ini; Haiuis ov Hvmknoi'Iira. '_'()<) 



SLEEPING HABITS OP^ CERTAIN HYMEN- 

 OPTERA. 



By Nai'han Banks. 



'I'he various means by wliich insects rest have l)cen hut little in- 

 vestigated. Occasional notes have been ])ul)lishe(l, but often in con- 

 nection with other matter, so that it is extremely difficult to collate 

 the recorded facts. Since the Hymenoptera are among the most 

 assiduous, as well as the most intelligent workers, it is natural that they 

 should exhibit some interesting habits of sleep. The idea that the bee 

 sleeps in the flower seems to have invaded literature at an early date. 

 And there are a number of bees that commonly do remain in llowers 

 (such as those of cucurbits and cami>anulas) all night. Whether this 

 is a natural rest has not, I think, been considered, It may be that the 

 insect remains, because, when ready to depart, it finds that it cannot 

 see. The resting or sleeping hal)its of ants have been treated by vari- 

 ous writers. That certain bees and fossorial Hymenoptera rest under 

 ])eculiar conditions appears to have been known for many years, but 1 

 cannot trace out much literature on the subject. An article by Mr. 

 K. A. Schwarz, referred to below, seems to be the mo.st extensive ])ai)er 

 published on this phase of insect sleep. 



(^ne July evening last summer, while engaged in wheeling the baby 

 (another one this time) through some tall grass in the corner of my 

 yard, 1 noticed an Aimnophila attached to a grass-stem in the |)eculiar 

 attitude shown in the accomjianying figure. In a moment I S'W 

 another, and soon found that I had invaded the sleeping (piarters of 

 several dozen Animophilas. While looking at various specimens I 

 noticed two species of bees, which Mr. Ashmead (who has kindly 

 named all the Hymenoptera) informs me are Epeoliis >ri>it\ujl/ts and 

 Mclissodcs biniaciilala, attached to the grass-stems and evidently asleep. 

 Although it was not yet dark these insects were easily caught by sim|>ly 

 placing a vial over them. In walking around I discovered asj/ecimen 

 of Mvziiie fastened to the stem of a wild onion |)lant, in the manner 

 described below. The Aininophilas proved to belong to two spec ies, 

 and on a later evening I took a third form. So that here were six 

 species of Hymenoptera representing three widely separate genera 

 using a small patch of grass as their sleeping cpiarters. Night after 

 night I examined this patch and found the same species, ;ilthough 



