158 FUMIGATION METHODS 
have done for me and to tell you that the experiment 
was a grand success.”’ 
A careful examination of the material sent showed 
seven species of dead insects, as follows: (1) Flour 
moth, Lphestia kuehniella, adults and larve; (2) 
bolting-cloth beetle, Zenxebvotdes mauritanicus, adults; 
(3) American meal worm, TZenebrio molitor, adults; 
(4) flour weevil, TZ7ibolium confusum, adult and 
larvee; (5) black carpet beetle, <Attagenus piceus, 
adult; (6) a lady beetle, and (7) a hemipterous insect. 
The latter two were, no doubt, feeding upon some soft- 
bodied creatures, as they are both predaceous. ‘This 
web, flour, dust, and insects was placed in a breeding- 
cage and was under daily observation for three weeks 
and no life made its appearance. When the package 
was received one living specimen of the flour weevil, 
Tribolium confusum, was found. It was, no doubt, a 
straggler from some crack where the death atmosphere 
did not reach. 
From recent results we are convinced that this gas 
is one of the most powerful and penetrating materials 
ever used in a mill or other buildings for the 
-destruction of vermin. It diffuses so readily that it 
will permeate all parts of a mill or enclosure in a few 
minutes. It is a deadly poison if inhaled by a human 
being, it is true, but there is no necessity of one 
breathing the fumes if the proper precautions are 
taken. The writer is satisfied that by its use many 
a miller can retain possession of his mill who would 
otherwise be obliged to give it up and acknowledge, in 
the ‘‘struggle for existence,’’ ‘it is the ‘’ survival of 
the fittest’’ that wins out. It is humiliating, indeed, 
