THE BOLL WEEVIL PROBLEM. 37 
save in such exceptional circumstances it will now be better to allow 
the leaf-worm to work unrestrictedly. . 
It has been suggested by Mr. Wilmon Newell that in special cases 
where there are difficulties in the following of the fall destruction of 
the plants, it may be advisable to take means to encourage the leaf- 
worm. This could be done by breeding larvee and pupe to be scat- 
tered in the fields and by carrying the pupx from localities, as the 
hills, where they appear first, to the valley fields, which are normally 
not reached until some time later. 
DESTROYING THE WEEVIL IN COTTON SEED. 
It has been abundantly shown that cotton seed is of importance as 
a medium through which the weevil may be carried. Many indi- 
viduals that happen to be carried to the gin on the cotton pass unin- 
jured through the gins to the seed houses. Consequently every seed 
house connected with a gin in the infested territory harbors more or 
less weevils, depending upon the amount of cleaning the staple is 
given. Of course such seed is exceedingly dangerous when taker 
into uninfested regions. Undoubtedly the present absolute embargoes 
against cotton seed from the infested region are wise. In general, 
they should be strictly construed. In some special cases, however, 
when. for instance, it is desired to obtain special improved seed. 
proper precaution can be taken to destroy all weevils by means of 
fumigation with carbon bisulphid. The method was described by the 
writer in Farmers’ Bulletin 209, from which the following is quoted: 
The following plan for this work is proposed: A tight matched-board box 
should be provided having sides 4 feet high, open on top, and of other dimen- 
sions to accommodate 12 or more 100-pound sacks of cotton seed placed upright 
upon the bottom. Another tier of sacks could be added if desired. Into each 
one of these sacks about 1 ounce of carbon bisulphid should be forced by an 
apparatus for volatilizing the liquid and mixing the vapor with air. The ac- 
companying illustration (fig. 9) will give an idea of this apparatus. It should 
consist of three essential parts, as shown in the illustration. A is an air pump 
having sufficient storage capacity to enable it to maintain a steady discharge of 
air for several minutes without continuous pumping. The stopcock at ad, regu- 
lates or prevents the escape of air, as may be desired. B is an ordinary 2-quart 
bottle fitted at bi: with a tight stopper of good length, having two openings, 
through which the inlet and outlet pipes pass. These pipes may be of glass or 
metal and should be as large as can be used. The inlet pipe, 02, reaches nearly 
to the bottom of the bottle and is provided at the lower end with a perforated 
metal cap as large as will pass through the neck of the bottle. This allows the 
escape of the air in small bubbles and insures rapid evaporation. The outlet 
pipe, bs, reaches only through the stopper. Upon the outside of the bottle is 
pasted a paper marked with 1-ounce graduations. C is a piece of ordinary 
2-inch iron gas pipe about 33 feet long, but this may be any desired length. It 
is closed and roundly pointed at the tip and for about 15 to 18 inches of its 
Jength provided with small perforations pointing in all directions to give free 
escape to the vapor into all parts of the sack of seed at once. 
512 
