176 
Psyche 
[September 
back. In reality, however, the pollen-baskets were over- 
flowing, and masses of pollen adhered to the underside of 
the body, while the legs were held close to the body, prob- 
ably holding the abdominal masses in place, with the result 
that the little bee had the appearance of being very fully 
laden indeed. 
Up to August 20th, most of the white-banded bees were 
still making their burrows and chimneys on the surface 
plane, and only about ten per cent of them were beginning 
to dig into the vertical face of the bank. In the case of this 
species, probably as soon as one nest was completed another 
was begun. 
Most of the turrets made by this species (figs. 9E and 
13) had a longitudinal split extending almost the full length 
of the upper side along its center. The purpose of this, as 
well as the purpose of the whole chimney, has often puzzled 
me. I have wondered whether the cause of this was mechan- 
ical or psychological, but after having observed the method 
of making the chimney, I have concluded that the opening 
along the middle of the chimney may be accounted for as 
mechanical. The bee backs out with a large ball of mud 
under her throat ; with the forelegs she divides this load in 
half and passes one portion backward under the body until 
it reaches the tip of the abdomen. This is applied to the 
edge of the turret, commencing at the bottom and working 
toward the top. This amount of wet clay is usually about 
enough to make half a ring. Then likewise the second half 
is passed beneath the body to the rear legs, the bee begins 
at the bottom again, joins this wet mass to the end of the 
first half of the ring and works upward in the opposite di- 
rection, perhaps with the intention of completing the ring, 
but rarely doing so. Since the second portion does not quite 
reach the first, there is a discrepancy, and the result is that 
layer after layer of this leaves an open groove on the top of 
the turret. It is possible that this is done purposely, and 
that the insect could just as easily carry out a little more 
mud or stretch what she has so as to complete the circle if 
she wished to do so. It may be that it is of advantage to 
build the nest so that it will admit the light, and this pecu- 
liarity of construction has become a habit. It is very pretty 
