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lands would be apt to show its effect more distinctly. There may also 

 be some obscure influence peculiar to the natures of the different soils. 

 It will be seen, therefore, that the experiments have fallen far short 

 of settling the whole problem, yet it seems to me that they have been 

 carried as far as profitable, and the matter is now in proper state to be 

 taken up by the intelligent farmer, whose experimental plats are his 

 fields. And it may be added that this is done with a feeling on my part 

 that whatever of truth there may be in the matter will stand as a nu- 

 cleus about which others may build, while whatever there may be of 

 error will as surely disappear. 



THE EFFECT OF THE LARVJE ON THE PLANTS. 



The effect of the larvae, especially on the young plants, does not ap- 

 pear to be generally understood, and I have myself been able to verify 

 either the figures or descriptions of Fitch and Packard only in excep- 

 tional cases. The swollen bulb just above the roots in Fitch's figures 

 gives but a vague idea of the true appearance, while Packard's figure 

 represents plants which have very evidently sprung from seeds only 

 slightly covered by the soil. Besides, the former figure only represents 

 the condition of the plants long after the larva3 have done their work, 

 and the latter, aside from the shoot being shorter, gives no idea of the 

 appearance of an infested stem, as found in nature, growing in the fields. 

 The yellow color of the foliage — there is usually more brown than yellow 

 about it — appears later, after the larvae are full-fed, and then it is largely, 

 at least, confined to the younger leaves, the older ones, under whose 

 sheaths the larvae occur, are killed by the freezing weather of winter. In 

 Circular No. 2 of the Agricultural Experiment Station of Purdue Uni- 

 versity I have given a representation of an infested plant fresh from the 

 field drawn from nature. The plant had been attacked soon after its ap- 

 pearance above ground and had not tillered. The leaves under these 

 conditions are broader, darker green, more vertical and bunchy. The 

 youngest leaf on a healthy plant as it unfolds and pushes upward is of 

 a tubular form and spindle-shaped, somewhat as represented in Pack- 

 ard's figure of a healthy plant. In the case of an affected plant, the 

 stem having been destroyed below ground, the spindle-shaped central 

 leaf is always absent. The difference between a healthy and infested 

 plant is shown by a comparison of figures. If a plaut has already till- 

 ered, each of the identical laterals, as they are attacked, will begin to 

 take on the form and color above described. It is, therefore, not only 

 possible to detect an infected plant without removing it from the 

 ground, but also to determine the individual tiller infested. Now, while 

 this feature of infested plants is so very clearly marked, at least after 

 the larvae are one-third grown, and from an economic standpoint of so 

 much importance that it is surprising that it should have been over- 

 looked, yet I can not myself lay claim to the fact by right of discovery, 

 as it was pointed out to me by a farmer in the autumn of 1884, and was 



