214 SOME BRITISH WILD BEES. 



various times, and, allowing for a slight difference in dates, 

 which of course is immaterial, my researches, as far as they 

 go, seem fully to bear out his idea. It is, I believe, a unique 

 habit, peculiar to Halictus and the nearly allied genus 

 Sphecodes, that a solitary bee should hibernate. 



The nest of this bee shows great industry on the part of 

 the artisan. Although not a social insect in the strict sense 

 of the word, yet it is very gregarious, one bank generally 

 being, if the home of one, the metropolis of hundreds. The 

 entrances to their burrows usually face the sun, and consist 

 of a little tunnel running horizontally about five or six inches, 

 with branch cells of an oval shape lying to the right and 

 left of the main passage. The tunnel and cells are smoothed 

 very carefully, and afterwards lined with a viscid secretion. 

 Each cell is furnished with a little lump of pollen, nearly 

 filling the cavity ; and upon this, near the base of the cell, 

 is laid the egg. The larva takes about twelve days to end 

 its first stage, and changes into a pupa ; in about five weeks 

 from birth the imago appears, generally making its exit 

 into the world about the end of August. It is stated that 

 these insects burrow during bright moonlight nights ; but 

 this I did not see. I never saw them excavating during 

 the day, but always engaged in collecting pollen. 



Like many another hardworking inhabitant of this world, 

 Halictus is greatly troubled with parasites which fatten 

 at its expense, literally taking its children's bread. Such 

 an intruder is the wasp bee, Nomada varia, a true cuckoo, 

 which lays its egg on the pollen provided for the offspring 

 of Halictus, and profits by that which cost her no labour. 

 Bolder robbers, such as Cerceris and Philanthus, capture the 

 living insects and carry them off to feed their young. A 

 very favourite resort in the autumn for Halictus is the 

 flower of the yellow ragwort, Senecio jacobcea ; had I been 



