136 Psyche [December 



pore, first with water-proofing and afterwards with clay. Thus 

 all communication with the outside world was cut oflF before the 

 egg ever hatched. 



I do not know how to account for Mr. Kellogg's observation 

 that "food is carried to the young in the open cell." (c/. Kellogg, 

 American Insects, p. 516.) I observed two hundred or more of 

 these cells and all were sealed tightly with egg and provisions. 

 More than a hundred of these sealed cells were kept in my labora- 

 tory until the emergence of the adult the following spring. 



After provisioning one cell, the same bee probably constructed 

 and provisioned others, as there were usually found from two to 

 five cells at the bottom of each tunnel, some placed one above 

 another, while others were set side by side. A large number of cells 

 were opened and were found to contain all stages of the young 

 insects from the egg to the almost mature larvae. These young 

 were kept in open cells or transferred to artificial wax cells, or, in a 

 few cases, the mature larvse were placed upon dry sawdust and 

 kept in the laboratory until they matured or were destroyed by 

 fungi. In this way their development was observed thru all of its 

 stages. About a hundred cells were preserved unopened in a cigar 

 box. 



Upon hatching, the larvse feed and grow rapidly for about three 

 weeks, by which time their growth is complete. Then they enter 

 upon a resting stage which lasts about nine months. During the 

 early part of this period of inactivity there is a gradual and slight 

 change in form, resulting in the partial disappearance of segmental 

 rings in the anterior region of the body, but there is no movement 

 exhibited during the entire nine months save a slow return of the 

 larva to its natural form when pressed out of shape. At the end 

 of this period or at the age of about ten months it accomplishes its 

 first moult and enters upon the pupa stage. About seven or eight 

 weeks later it moults again, reaching the adult stage but a few days 

 less than a year old, whereupon the bee chews its way out of the 

 cell. 



On Angel Island, two years later, a very extensive aggregation of 

 these bees was found by the writer but further study was at the 

 time impossible. On a steep bank, facing south at the shore of the 



