BURROWING AND CARPENTER BEES 



along which, following the grain of the wood, she will 

 rasp out a new tunnel in which to establish her house- 

 hold. 



The tunnels of the carpenter bee are straight, cylindri- 

 cal tubes, cut out quite smoothly, about one-half inch 

 in diameter, or a little longer than the bee herself. 

 Sometimes, in the case of re-used tunnels, the tube will 

 be longer, having been widened, probably, to get material 

 to form the cell portions. The longest tunnel I have 

 measured, shown on page 176, was sixteen inches, and 

 there was a branch five inches long. The main tube 

 was three-fourths of an inch wide, and the vestibule a 

 half-inch long. Judging by the ringed elevations that 

 marked the locations of the cell partitions, nineteen cell- 

 fuls at least had been reared in this nest, which had 

 doubtless seen several summers' use, and there were six 

 cells in the branch. 



The bee, of course, works with her head inward, 

 and throws the gnawed pellets behind her, like a dog 

 digging after moles or ground-hackees. When the tun- 

 nel is finished, she marks off a section about her own 

 length and places therein an egg, and adds a piece of 

 bee-bread, which fills up about half the space. Then 

 she closes the section with a solid, circular partition, 

 slightly concave on one side. This is made out of the 

 sawdust gnawed from the tunnel, mixed with a gluti- 

 nous secretion or saliva, which hardens and forms a sort 

 of wood composite. The section thus sealed up is a 

 breeding-cell. This done, the mother fits out another 

 similar cell in the same manner, and adds cell to cell 

 until her quota is filled, which will be half a dozen, 

 more or less. 



The eggs thus deposited become in due time small 



177 



