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aged. The second plat was even worse injured than the first, and the 

 third much worse than either of the others. The fourth appeared to be 

 almost as badly infested as the third, but it had only partly tillered, 

 and hence there was a better prospect for it to throw up unaffected 

 shoots. The fifth had not tillered, and was only very slightly infested, 

 with very young larvae, while the sixth was not yet up. 



On April 12, 1888, the plats were visited again. About 25 per cent 

 of the plants on the first three plats appeared to have survived. The 

 fourth was apparently 50 per cent better, the fifth was in almost 

 as good shape as the fourth, while the sixth was backward, the plants 

 being small and thin on the ground. 



The estimate yield, made by Mr. Banks at time of harvest, on 

 the basis of 20 bushels per acre as an average yield, was as follows : 

 First plat, 50 per cent; second, 50 per cent ; third, 65 per cent ; fourth, 

 90 per cent; fifth, 70 per cent. The remainder of the field was sown 

 on September 2, and shared in the destruction in common with plat 

 3. Another field at some distance from this was sown about Septem- 

 ber 20 and sustained no material injury. 



It will be observed that the first three plats were sown almost at the 

 same time as the first three at La Fayette, yet stubble from the first 

 three plats at La Porte, collected on September 2 and placed in a breed- 

 ing cage beside another containing stubble from the first three at La 

 Fayette, gave adult flies nearly a week earlier. In other words, the 

 majority of the adults from Mr. Banks's plats emerged prior to Septem- 

 ber 15, while those from my own did not reach their maximum num- 

 bers until after the 15th, and from then on till the 25th. In both 

 cases, however, a few stragglers emerged occasionally until early in 

 October. As previously stated, the plats of 1888 were not properly 

 sown, Mr. Banks not being able to attend to them himself; but a visit 

 to the locality on November 8 revealed but very little injury to wheat 

 which had been sown after the middle of September. 



The experiment plats of 1890 were sown September 1, 10, 20, 30. 

 These were examined late in October and fully substantiated the ex- 

 periments of previous years. The sowing of September 1 was consid- 

 erably injured, while that of the 10th was very seriously affected, as 

 was also a large field adjoining sown but a day or two later. The sow- 

 ing of September 20 was comparatively free from attack, while that 

 sown September 30 appeared to have almost entirely escaped injury. 



The sixth and last series of experiments were made for me by Hon. 

 J. N. Latta, at Haw Patch, Lagrange County, in about the same lati- 

 tude as La Porte. The sowings were made in 1887, the first being 

 drilled on July 28, but owing to drought the plants did not appear 

 above ground until about the 28th of August. The second plat was 

 sown on August 15, but came up the same time as the first ; the third, 

 sown September 1, came up September 6; the fourth, sown September 

 12, came up September 21 ; the fifth, sown September 24, came up the 



