15 
i)eing- here much greater pests than in their native homes. This result 
is due in part, at least, to the fact that their native parasitic and pre- 
daceous enemies have not been introduced along with them, and they 
are thus able to develop largely unmolested by these important checks. 
The proposition, therefore, has been to determine the original home 
of an injurious introduced species, and then to obtain its enemies and 
to array them against it in hope of thereby securing its control. 
Regarding the insect under discussion — the cotton bollworm — there 
are but few data with a possible bearing on its native home, and these 
are largely of a contradictory nature. That it is really indigenous 
over its present extended range is scarcely to be admitted. While 
there are numerous truly cosmopolitan families and a large, though 
proportionately less, number of genera, the truly cosmopolitan species 
of animals are comparatively few. In the case of many widely dis- 
tributed insects the possible accidental influence of man in furthering 
their distribution really makes it doubtful whether they are indigenous 
throughput their known range. Afiosia i)lexlp2)us Linn, and Yanessa 
(Pyrameis) cardui Linn., among butterflies, appear to enjoy an almost 
world-wide distribution, but the ease with which pupiB of these could 
be transported and, further, the vigorous flight of the butterflies 
themselves when once established would enable them to soon become 
|[uite common over an entire continent. 
Reference to Plate I will show how widely the bollworm is at pres- 
nt known to be distributed over the world. Rejecting the idea of its 
>eing truly indigenous over this vast territory, it may be worth while 
o consider some facts bearing on the subject of its original home. 
As has been noted in the original description of this species by Fabri- 
cius under the name Boiribyx obsoleta^ its habitat is given as Americse 
Meridionalis Insulis. Accepting the identity of Bomhyx ohsoleta with 
our bollworm moth, as held by Sir G. F. Hampson and others, the 
species was first described from a specimen or specimens probably from 
the West Indies. Apparently the earliest reference to the bollworm 
as depredating on crops comes from the United States. B}^ 1820 its 
ravages on cotton were the occasion of a short note in the American 
Farmer b}" a correspondent writing under date of September 20, 1820, 
to the efi'ect that the pods of his cotton had been attacked by a large 
green worm from 1 to 1^ inches long, which ate its way into the pod 
and did not leave it until it had completed the destruction. Some of 
the worms were smaller; some were brown and red. The injury 
seemed to be severe, with the prospect of one-fourth of the crop 
being destroyed. 
y 1811 the bollworm had become prominent as an enemy to cot- 
ton and corn in the Southern United States, and it is recorded as 
attacking corn in Illinois in 1812. 
22051— No. 50—05 2 
