THE PINK BOLLWORM. 5 
The collection which I have was secured from the seed room of one of the 
ginneries in Shanghai and from the fields at Tungchow, about 12 hours' ride 
by boat up the river from Shanghai. The infestation is more or less general 
throughout China ; however, there may be some small areas where it is not 
present. A majority of the cotton grown within a radius of 100 miles of 
Shanghai is shipped into that port before being ginned, and from evidences 
found at the ginning establishments there is no doubt but what all those re- 
gions are infested. In fact, the larvse are so numerous that by going into the 
seed room of the gins a person may secure any number of them within a very 
short time, as they may. be seen crawling around over the seed and on the 
walls. 
PRESENT DISTRIBUTION IN MEXICO. 
As far as absolutely definite evidence shows, the pink bollworm 
is confined to three localities in Mexico, one of which is the Laguna 
district, a valley isolated by mountain ranges about 200 miles from 
the Texas border. The Laguna. in which the bulk of the total Mexican 
crop is produced, consists of about 1,200 square miles of land. Mr. 
August Busck, on a trip to Mexico in the early part of 1917, ob- 
tained samples of cotton seed from 40 of the estates in that region. 
Thirty of these samples were found to be infested and later records 
indicate infestation on ranches from which no insects in the seeds 
were received. In short it is evident that through the shipment of 
cotton seed from one part of the Laguna to another and possibly 
through the flight of the insect, the pink bollworm has become gen- 
erally established there. Although the distribution of the pest is 
naturally irregular at the present time, it is certain that it will be- 
come uniform in the course of a few years, and that most energetic 
steps must be taken by the planters to control or eradicate the insect. 
Other localities known to be infested in Mexico are Allende, about 
40 miles south of Eagle Pass, and the Trevino ranch, immediately 
opposite Del Eio. In both cases the infestations were the result of 
the receipt of seed from the Laguna. 
NATURE AND AMOUNT OF DAMAGE. 
The pink bollworm affects cotton production in several ways. In 
the first place it destroys a certain number of bolls or portions of 
bolls, in which case the lint produced is short and kinky (fig. 1) . The 
injury, however, does not end with the reduction in the yield of 
lint. The crop of seed is correspondingly reduced, and what is ob- 
tained is of light weight and poor grade, In the crushing of 
Egyptian seed in England it was found that the oil content was 
lower than normal by about 20 per cent, and that the oil actually 
secured was of dark color and comparatively low value. The work 
of the insect is also of importance in connection with seed for plant- 
