APIARI^E. 133 



"The tunnels are sometimes taken possession of by other 

 bees and wasps. I think when this is the case, the Xylocopa 

 prefers making a new cell to cleaning out the mud and rubbish 

 of the other species. I frequently find these bees remaining 

 for a long time on the wing close to the opening, and bobbing 

 their heads against the side, as if fanning air into the opening. 

 I have seen them thus employed for twenty minutes. Whether 

 one bee, or more, makes the tunnel, that is, whether they take 

 turns in boring, I cannot say at present. In opening the cells, 

 more than one are generally found, even at this season. About 

 two weeks ago, I found as many as seven, I think, in one." * 



The hole is divided by partitions into cells about seven-tenths 

 of an inch long. These partitions are constructed of the 

 dust or chippings made by the bee in eating out her cells, for 

 our active little carpenter is provided with strong cutting jaws, 

 moved by powerful muscles, and on her legs are stiff brushes 

 of hair for cleaning out the tunnel as she descends into the 

 heart of the solid wood. She must throw out the chips she 

 bites off from the sides of the burrow with her hind legs, pass- 

 ing the load of chips backwards out of the <;ell with her fore- 

 limbs, which she uses as hands. 



The partitions are built most elaborately of a single flattened 

 band of chips, which is rolled up into a coil four layers deep. 

 One side, forming the bottom of the cell, is concave, being 



* " Since writing the above I have opened one of the new holes of Xylocopa 

 which was commenced between three and four weeks ago, in a pine slat used in 

 the staging of the greenhouse. The dimensions were as follows: Opening fully 

 3-8 wide ; depth 7-1(5 ; whole length of tunnel 6 and 5-1(5 inches. The tunnel branched 

 both ways from the hole. One end, from opening, was 2 and 5-8, containing three 

 cells, two with larva and pollen, the third empty. The other side of the opening, or 

 the rest of the tunnel, was empty, with the exception of the old bee (only one) at 

 work. I think this was the work of one bee, and, as near as I can judge, about 

 twenty-live days' work. Width of tunnel inside at widest JMG inch. 



For some days this bee has been discharging a great quantity of saw-dust and 

 pollen, which I had collected by placing a vessel under it. It would seem that she 

 had cells constructed also in the opposite side of the hole, and that she removed 

 them to enlarge the tunnel. Among the stuff thrown out, I find a partition of a cell 

 nearly entire. 



I have just found a Xylocopa bobbing at one of the holes, and in order to ascer- 

 tain the depth of the tunnel, and to see whether there were any others in them, I 

 sounded with a pliable rod, and found others in one side, at a depth of live and one 

 half inches; the other side was four inches deep, without bees. The morning was 

 cool, so that the object in bobbing could not be to introduce fresh currents of air, 

 but must have had some relation to those inside. The legs on such occasions are, 

 as 1 have noticed, loaded with pollen." American Naturalist, vol. 1, p. 370. 



