2 Mr. Newport on the 
observations made by myself on a curious deviation from its usual 
habits by the common leaf-cutter-bee— 
Megachile centuncularis. 
On the morning of the 19th June, 1829, I observed one of 
these busy little creatures conveying alternately portions of rose- 
leaves, and of some other material, which, at first, I could not 
identify, to a hole in a brick wall in our garden, where she was 
constructing her nest. The whitened and singular appearance of 
this new material induced me to watch her proceedings, to ascer- 
tain its nature. The quantity conveyed by her was fully equal to 
that of the rose-leaves, and it seemed to be regarded by her with 
quite as much attention. On examining her proceedings very 
closely, which I had an opportunity of doing, as the nest was ad- 
vanced towards the entrance of the hole, I was much amused at 
the precision with which she seemed to adjust her materials. On 
one occasion, after being for some time engaged in the hole, she 
came to the entrance for a few seconds, and seemed as if survey- 
ing the interior, and then again proceeded to the bottom of the cell. 
After she had remained there for some time, she suddenly brought 
out a piece of the white material and dropped it on the outside of 
the nest as if unfitted for her purpose, and then flew away, and 
in a few moments afterwards returned with a portion of rose-leaf. 
On examining the material rejected by her, I was surprised to 
find that it was a little piece of cotton cloth, very finely carded, or 
picked to pieces, and which I at first supposed had been substi- 
tuted for some other material usually employed by her. In the 
early part of the following day she had made good progress 
with her labour; I saw her at work very soon after four o’clock 
in the morning, when she was bringing in rose-leaves, and also 
cotton, as on the previous day, with great assiduity; and she con- 
tinued to do so until about ten o’clock, after which I missed her 
for nearly two hours. At that time I suspect she was engaged in 
the business of oviposition. The interior of the nest seemed 
then to have been nearly completed, and the hole was partially 
lined with cotton at its entrance. Soon after twelve o'clock I 
again saw her; she was then heavily laden with pollen. At one 
o’clock her activity was increased, and rose-leaves alone were then 
conveyed to the hole with great rapidity, and continued to be so 
until the nest was completed. At this stage of her labours I 
carefully noted the length of time that elapsed from the moment 
of her leaving the nest to her return to it laden with rose-leaf, 
and was astonished to find that it never exceeded forty-five seconds, 
