BURROWING AND CARPENTER BEES 



summer residence upon the field. This bee is a brilliant 

 metallic blue in color, and spends practically all its 

 life under ground. The remarkable burrowing power 

 of Colletes is doubled by Augochlora, for one tunnel 

 was found over five feet deep ! 



Mr. Brakeley, intent upon comparing the relative 

 working powers of a human athlete with those of this 

 insect, put the matter thus: A blue bee weighing less 

 than one grain will dig a hole double its own diame- 

 ter sixty-four inches deep. How much ought a college 

 athlete weighing (say) 185 pounds or thereabouts, with 

 a diameter of two feet (more or less), be able to bur- 

 row without tools in order to equal the blue bee, weight 

 for weight? His answer is, a tubular tunnel 1295 miles 

 deep and four feet wide! And that is only half the just 

 estimate, for when it was made it was not known that 

 the bee really makes two similar burrows during its life ; 

 moreover, no account is taken of sidings for the cell 

 clusters, which largely increase the labor. 



The entrance to the blue bee's nest is always under 

 some bit of natural protection, such as a tuft of grass 

 or moss or lichen. Hence, by a short arm, the burrow 

 runs obliquely to the main shaft. In carrying her 

 diggings, the little miner squeezes the released pellets 

 against her breast and abdomen, then carefully creeps 

 upward to the entrance and dumps her load literally by 

 a somersault. This leaves her with head to the gate, 

 and, without the delay of turning around, she hurries 

 down to her task. Meanwhile a low moundlet grows 

 around the entrance. 



Her cells are made in small clusters, of which the 

 central one and sometimes others are converted into 

 nurseries; but commonly these are surrounded by 



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