June 4,1917 
The Pink Bollworm 
361 
More effective parasites of P. gossypiella might be expected to be found 
in the original home of the species, Africa, but no record of such has been 
made. 
It is also possible that the congeneric species, P. malvella y found in 
Europe and Africa, or any other lepidopterous species with similar biol¬ 
ogy, may be preyed upon by parasites which could become of value 
against the pink bollworm. 
An egg parasite would be by far the most promising for effective results, 
first, because the egg is the‘only stage of the species which is easily 
reached by a parasite, and, secondly, because the insect is thus destroyed 
before it has had a chance to do damage. As soon as the larva has bored 
into the boll, it is reasonably safe from parasites, and, even if killed, has 
already done serious damage to the boll. Trichogramma minuta Riley, 
which is parasitic on the eggs of the codling moth in this country, or any 
other species parasitic on singly laid, exposed eggs of Microlepidoptera, 
would be worthy of trial. 
OTHER NATURAL ENEMIES 
There are no predacious insects playing any r 61 e in the reduction of 
P. gossypiella in the Hawaiian Islands, and it is doubtful whether any 
such insect could be of economic value. The larvae within the bolls are 
quite safe from them; and the numbers of moths which, for example, 
a mantis could catch would be quite negligible. 
Large numbers of the predacious mite Pediculoides ventricosus Newport 
were found in a few instances in cotton bolls in Honolulu, and they had 
invariably killed the P. gossypiella larvae present. This mite has also 
been received from Brazil with the remains of larvae of P. gossypiella 
which it had destroyed. It is also recorded as an enemy of the pink 
bollworm in Egypt (33), but it seems doubtful that it can ever be really 
effective in the field against P. gossypiella. If in exceptional cases it 
should become sufficiently numerous to be a check on the pink bollworm, 
its presence would probably be so obnoxious to the workers in the field 
as to counteract its Value as a parasite. In stored cotton this predator 
might readily have some effect in killing off the hibernating larvae, but 
the same results may be obtained in a quicker and surer way by fumiga¬ 
tion, and it is not believed that Pediculoides ventricosus can be success¬ 
fully employed in any organized fight against the cotton pest. 
There are very few wild birds in the cotton fields of the Hawaiian 
Islands, and they play no r 61 e in keeping the pest in check; but domestic 
fowls are of some benefit. In one cotton plantation on the Island 
of Oahu a large number of chickens, ducks, and turkeys had free access 
to certain inclosed areas of cotton. These birds materially assisted in 
the reduction of the pest by eating a large number of the moths and such 
larvae as accidentally fell to the ground. 1 
1 Vosseler (7) records that chickens and ducks voraciously picked up P. gossypiella larvae which made 
their escape from the bolls placed on a sheet in strong direct sunlight. 
