104 
Psyche 
[June 
either, for already she had made attempts to get out by biting 
away the pith at the side. 
As I watched her more, closely at this part of her task I dis- 
covered that all of her biting and tugging was not for the one 
purpose of shredding the fibrous plug, but of moving it whole; 
even as I watched her she was, with jerk after jerk, working it 
slowly downward to a point where she had removed pith to 
loosen its pressure against the walls. I watched intently, doubt- 
ful of her success; but she knew her business better than I, and 
after an arduous session, a bite here and there and a jerk this 
way and that, she eventually succeeded in turning it up edge- 
wise and pulling it downward as she crept past it, in a depression 
in the pith at the side; then she kicked it down among the other 
debris at the bottom. Thus my pretty theory, that she was dig- 
ging in the pith at the sides to escape by going around the plug, 
like Prosopis modestus , was left in uncertainty, since now she 
had moved the whole plug bodily below, only cutting out enough 
extra space to permit the passing of her own body. 
Thus the roof of her cell was disposed of. I should have 
made clear earlier that each partition comprises two parts or 
layers, each made of a separate mouthful of fibre; these discs, 
each about 1/8 inch thick, are near together but separate, one 
forming the roof of one cell and the other the floor of the cell 
above. Now that this bee had removed the roof of cell No. 2, 
she did not stop but went right on attempting to remove bodily 
the floor of No. 1 also, when a most interesting thing happened. 
She went to the left wall and bit out a small amount of pith 
adjacent to the disc, thereby enlarging the channel by perhaps 
1/8 inch, again she attempted to remove the plug, but still it did 
not yield; so she went to the opposite wall and nibbled there a 
little also, and again tried to jerk the obstruction loose. 
Thus she continued for a half-hour, directing her blows upon the 
plug and her bites principally upon the left wall, and occasionally 
a few nibbles on the right wall; all the time the rasping noise 
made by her mandibles was distinctly audible. I was called 
away for a few minutes, and meanwhile the wonderful thing 
2 To be published later. 
