v] BEES 69 



the same fashion as the Andrenas which do not issue 

 from their burrows at all until the spring. These 

 female Halicti were hatched out in the late summer 

 of the previous year, at the same time as their brothers 

 and husbands who are so much in evidence at that 

 season ; after pairing and there is evidence that 

 pairing often takes place within the burrow and that 

 the female (like Andrenas) does not in such cases 

 come out into the open the female at once retires 

 into the burrow and there hibernates, having made 

 no cells nor stored any provisions either for herself 

 or her offspring. The males all die off before the 

 winter. In the following spring the female wakes up 

 and at once sets about the work of constructing 

 burrows and provisioning cells with pollen and honey, 

 and of laying eggs. 



In other species, e.g. H. mono, a very common 

 British form, it appears that there is only one genera- 

 tion in the year, but the period of emergence is very 

 extended, lasting over several months. 



Both Halicti and Andrenae are very subject to 

 the attacks of a small parasitic insect, usually regarded 

 as an aberrant beetle, named Sty lops. The head of 

 the parasite is often visible projecting between the 

 abdominal segments of the bee ; the body is lodged 

 among the viscera of the "host" and absorbs nourish- 

 men t from them. The female Stylops reaches maturity 

 within the bee's body and never leaves it ; the male, 



