[48] REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 



adjoined cotton on one side eaten bare, on the other almost untouched. My object 

 was to see whether I could stop their progress, moving as they were from west to east. 

 Have long held the opinion, confirmed by observation, that it never leaves the stalk 

 upon which the egg is deposited to eat again. I there saw them crossing i public 

 road, leaving behind untouched cotton. 



October 10, examined cotton where I had previously dusted flour preparation and 

 found that no progress had been made in injury to the leaves, though found a few 

 young caterpillars; also, examined cotton upon which I had placed Boll Worms re- 

 moved from corn, but found no damage. My belief is that when transferred from 

 one plant to another they are either slow to eat or do not eat at all. Examined the 

 field sprayed on the 7th and found some worms still there, but a comparison with ad- 

 joining cotton showed that the pyrethrum had destroyed many. 



14th, examined the plot sprayed on the 2d instant, and found that undisturbed by 

 worms of any description, and found some dead worms upon the stalks. This plat 

 had also a fresher appearance than any surrounding cotton and was free from worms, 

 while Aletia could be found all around it. 



I will remark that the result upon pea vines, where the infusion was applied, was 

 exemption from worms, but at the same time must confess that I saw no damage else- 

 where. Though finding many leaves perforated, I did not find Heliothis larva upon 

 the leaves or pod, but occasionally found other caterpillars. 



To sum up, would say that, from my experiments and experience with pyrethrum, 

 if sprayed over cotton or dusted on the apex of the ear of corn so as to reach the 

 worms, in infusion or decoction, cold or hot, in the proportion of one pound to thirty gal- 

 lons of water, ©r one pound to ten of flour or ashes, it would effectually protect cotton 

 against either Heliothis or Aletia; but a stronger preparation, say one to twenty-four 

 gallons or one pound to eight pounds, would be more efficient, especially for large 

 Boll Worms. After being once touched with it, I think they cease to eat, sicken and 

 die. I would prefer always the spraying to the dry powder, for the reason that it 

 can be more generally diffused over the plants ; and furthermore, because it disturbs 

 the worm and would, in many cases dislodge it from the plant, and when once dis- 

 lodged or disturbed they seem to wander distractedly. 



As before remarked, Heliothis has not visited here in its wonted numbers in cotton, 

 and unless it has sought other vegetation, adverse meteorological conditions have 

 been in operation. 



I believe, however, successive crops of corn and peas, which have been a feature of 

 farming this season, may account for its absence in cotton ; and from this a hint may 

 be taken, which, if put in practical Operation, would insure the cotton crop against 

 damage from Boll Worm. Either hand-picking or the use of pyrethrum with the first 

 brood in corn would be a feasible operation with any planter. 



I would also say, unhesitatingly^ that any farmer, by the use of pyrethrum or other 

 poisons, can, by watching- the advent of the first brood of worms, which almost in- 

 variably occupies a small area, stop its ravages by a timely application, and at a 

 small outlay of either labor or money. 



Respectfully submitted, 



E. H. ANDERSON, M. D. 



Prof. C. V. Riley 



