136 THE HUMBLE-BEE ; Vil 
allowed to enter and dwell in weak nests, not only 
of the species upon which they naturally prey, 
but of others. On June 22, 1910, I found a queen 
of B. ruderatus, that had lost the tip of one of her 
antenne, in a weak colony of B. pratorum that | 
~had placed in a domicile under a wooden cover 
in my garden. The fratorum queen was also 
in the nest, but she seemed feeble, and died the 
next day. Unfortunately the vuderatus queen dis- 
appeared. 
But whether a Bomdus queen could be got to 
lay eggs in the nest of an unallied species I am at 
present unable to say. If this were possible one 
could easily rear colonies of rare species, and study 
their habits from queens caught in the fields. 
PLACING QUEENS IN EMPTY NESTS 
The method of endeavouring to get a colony of 
humble-bees started that would occur to most people 
would be to place a queen in an empty nest in the 
hope that she would adopt it. Many times have 
I tried this, always (excepting on the occasions 
mentioned below) with the disappointing result 
that the queens flew away and never returned. 
When I was a boy I used often to catch a queen 
and put her into a box containing a nest. Some- 
times I fed her and shut her up for a day or two 
before letting her out, and then | always noticed 
that she circled around the spot marking it as she 
flew away, which seemed to show that she had some 
