196 Psyche [October-December 



Another of the 16 nests which was taken on September 11, 

 1922, contained (1) 31 males and about 50 workers of Bremus 

 im.patiens; (2) many adults and larvse of Antherophagus ; (3) 

 a large number of spiny, dipterous larvse (probably those of 

 Fannia); and (4) numerous pseudo-scorpions {Chelanops sanhorni 

 Hagen (det. Mr. Nathan Banks). A few of these pseudo-scor- 

 pions were also found in one of the affinis nests. Mr. Nathan 

 Banks has informed me that Chelanops sanborni is frequently 

 found attached to the appendages of insects, especially those of 

 Diptera. This fact, together with the fact that all 3 nests in 

 which these pseudo-scorpions occurred, were at least 3 ft. below 

 the surface of the ground, and had exceptionally long tunnels, 

 suggests that Chelanops, like the beetles of the genus Anthero- 

 phagus, gets into bumblebee nests by phoresy (cf. Wheeler, 1919). 



Franklin (1912/13, I, p. 313) states that in the large nest 

 of Bremus impatiens taken by him, the majority of the cells 

 seemed to be entirely separate from one another. This was the 

 case with most of the 8 Breinus affinis nests which I took, but 

 it was not true of any of the 16 impatiens nests. 



In addition to the main tunnel, which was about \}4^ inches 

 in diameter, 3 of the most populous nests also had a narrower 

 tunnel, about | inch in diameter, leading to the nest from the 

 side opposite the main tunnel. Through this narrow tunnel, 

 probably made by the bees themselves, nesting material was 

 dragged in. In Europe, Wagner (1907, p. 11) found a similar 

 narrow, secondary tunnel in connection with a nest of Bremus 

 lapidarius, and concluded that it was constructed by the queen. 

 However it seems more likely that this passage, if made by the 

 bees, is excavated by the workers, and that it probably also 

 serves as a ventilating shaft, for Bremus lapidarius, like Bremus 

 impatiens, frequently has very populous colonies. 



A prosperous Bremus impatiens colony stores a considerable 

 quantity of honey and pollen. The latter, as in the case of 

 Bremus affinis, is sometimes stored in pollen cylinders. 



In the vicinity of Boston, the queens of Bremus impatiens 

 appear in large numbers in May, and most colonies are probably 



