1913] Xichols — Observations on the Nesting Habits of the Mining Bee 109 



apparently only in the early morning hours, for no bees were seen 

 bearing pollen in the middle or latter part of the day. Many 

 plants were blooming in the vicinity, wild Composite and Legumi- 

 nosse, also cultivated sweet peas and morning glories, but none of 

 them were visited by the bees. Since the heavy, sticky masses 

 brought back by them resembled in appearance the pollen of 

 Hibiscus moschatus, which grew abundantly in the swamps not 

 far away, it was suspected that this plant might be the source 

 of supply. A comparison under the microscope of Hibiscus pollen 

 with some taken from a nest proved this to be the case. 



Although the behavoir of the bees corresponds in general to the 

 foregoing description, some variation was observed. As is often 

 the case with solitary wasps, nests may be begun and abandoned 

 before completion. The wall of earth around the entrance is more 

 carefully built in some nests than in others, and the distance to 

 which the pellets are thrown also varies. Individual differences 

 in the ease with which the nest was recognized were also noticed. 

 Some fly with astonishing directness and rapidity to the opening, 

 while others alight at the wrong spot and appear confused. Bees 

 sometimes enter nests not their own, and, on discovering the mis- 

 take, back hurriedly out. Before emerging it is usual for the 

 insect to stop a moment at the opening, moving the head from side 

 to side as if reconnoitring. Slight movement or noise in the neigh- 

 borhood will cause her to jerk back into the nest, but after a short 

 interval, she slowly reappears, again reconnoitres and flies off. 

 Individuals differ in this respect also; some appear more timid than 

 others. 



On Nov. 29, I again visited the place, in order to determine if 

 possible how the bees passed the winter. No trace remaining of 

 the depressions marking the site of the nests, I was obliged to dig 

 at random. The quest proved not entirely fruitless and three 

 cocoons were obtained containing larvae. The cocoon is made of 

 densely woven silk entangling many left over pollen grains and 

 lined with a brownish varnish-like substance, well adapted to keep 

 out the dampness. The largest of the three measures a little 

 over two centimetres (about twenty three mm. by thirteen, the 

 smallest about thirteen mm. in each dimension and the third about 

 sixteen mm. by thirteen mm. This last was broken in removing 

 it from the soil. It contained a small larva not quite a centi- 



