The Young Queens 
the amelioration of each species through the 
triumph of the stronger. This struggle, 
as a rule, is most carefully organised. ‘The 
hecatomb of the weak is enormous, but that 
matters little so long as the victors’ reward 
be effectual and certain. But there are cases 
when one might almost imagine that nature 
had not had time to disentangle her com- 
binations ; cases where reward is impossible, 
and the fate of the victor no less disastrous 
than that of the vanquished. And of such, 
selecting an instance that will not take us 
too far from our bees, I know of no case 
more striking than that of the “ triongulins” 
of the Sitaris colletes. And it will be seen 
that, in many details, this story is less 
foreign to the history of man than might 
perhaps be imagined. 
These triongulins are the primary larve 
of a parasite proper to a wild, obtuse- 
tongued, solitary bee, the Colletes, which 
builds its nest in subterranean galleries. 
It is their habit to lie in wait for the bee 
at the approach to these galleries, and then, 
to the number of three, four, five, or often 
of more, they will leap on her back, and 
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