EXPERIMENTS ON THE COTTON-WORM. 49 
brood of worms was small. I watched closely, trying to discover the 
cause of the diminution. I conjectured that ants were devouring the 
young worms, and gave them close attention. One day I saw two small 
red ants (Myrmica molesta) bring a half-grown Cotton-Worm down the 
stalk of cotton. Upon examination I found the worm had been wounded, 
apparently it had been pierced, and it was almost dead. I could not 
tell whether the injury to the worm bad been done by the ants, or 
whether they had seized it after it had become helpless. After this, 
although I watched closely, with the impression on my mind that ants 
did in all probability destroy worms, I found at no time ants attacking 
or devouring them, nor did I see any indications to this effect. When 
I saw lines of ants traveling through the cotton-field I frequently dis- 
turbed their movements by breaking up their path in some way, and 
then I frequently put pup and larvee within easy access. Again, I 
oftentimes put worms and pup near them on the ground without dis- 
turbing them in any way. Lalso bro ught worms, pup. and ants to 
the laboratory and imprisoned them together, meanwhile feeding the 
worms. The cotton insects suffered nothing from the ants. I saw re: 
peatedly ants eating the cast-off skins of worms and the chitinous integ- 
uments of pups from which the moths had bursted. I saw ants around 
the eggs of Aletia, eating them; I think they eat the fresh eggs; I 
know they eat the membrane that covers the albuminous material of 
the egg, and I am pretty sure, from all I saw, that they devour the 
whole egg. This would explain the small brood of worms coming from 
such a swarm of moths, and I think this is the way they check the mul- 
tiplication of this enemy to the cotton crop. 
EXPERIMENTS ON THE EGGS. 
I frequently brought into the laboratory leaves of cotton bearing eggs 
of Aletia. The walls of the laboratory are thick, and the temperature 
there is never very high, even in midsummer. These leaves I disposed 
of in two ways: First, I put some in glass jars, on which ground-glass 
plate covers were lightly laid; second, others I shut up in cylindrical 
tin boxes, holding about a pint each, with tightly-fitting tops; these 
boxes were such as those in which buhach is sold. Of those put in 
glass cages none of the eggs ever hatched. If they did I could uot find 
the worm. The leaves quickly wilted, turned dark, and after a while 
became black, giving off the odors of decomposition. 
On the leaves put into tin boxes eggs hatched, and the worms were 
fed until they reached full growth, webbed up, and formed moths. 
When the tops were put on tightly the atmospheric communication 
between the inside and outside was very slow. The moisture and color 
of the leaf were retained for many days. These caged larve got no 
light, except when the tops were removed for taking out the refuse 
matter and the introduction of fresh food. It seems fairly inferable 
that, first, no very high temperature is essential to the hatching of the 
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