New York Aguicultural Experiment Station. 407 



the season. In the smaller varieties the disease usually appeared 

 in from two to four weeks after iuoculalion, but the uiiinoeulated 

 plants used as a check, likewise, invariably became atfected to 

 a considerable extent so that no trustworty information covild 

 be obtained from such experiments. 



Finally it became evident that the plants must be grown in 

 pots of sterilized soiJ if the inoculation experiments were to 

 furnish results of any A-alue. A quantity of soil was thoroughly 

 sterilized in steam sterilizers and j)laced in large pots. On July 

 Ji Early Cory sweet corn (grown in Iowa) was planted in the i>ots 

 and inoculation experiments with pure cultures of the yellow 

 germ were started. The pots were allowed to remain uncovered; 

 otherwise, all precautions were taken to prevent contamination. 

 Nevertheless, an undoubted case of the disease was found in one 

 of the check pots on August 3d, and later several others were 

 found. This meant that diseased seed had been used and the 

 experiment was worthless except to prove that infection may be 

 brought about by the germs which cling to the seed. 



Three unsuccessful attempts were made to produce the disease 

 in yellow dent field-corn by iiioculation. On xVugust 2()th, 1895, 

 ten plants of yellow dent corn (variety unknown) were inoculated 

 by puncturing the stem at the surface of the soil with a sterilized 

 scalpel and then inserting into the puncture a small quantity of 

 the yellow substance taken directly from the interior of the stem 

 of a diseased sweet corn jjlant. These plants were under obser- 

 vation until frost (about October 7th) but none of them showed 

 any symptoms of the disease. On July 12, 1897, twenty plants 

 of yellow dent corn, variety Oolden Dent, were inoculated in the 

 same manner as in the experiment of 1895. None of these plants 

 developed outward symptoms of the disease, but a month after 

 inoculation it was found that in several of the plants the yellow 

 bacillus had ascended a few of the fibro-vascular bundles where 

 it was visible to the naked eye as far as the third node above the 

 point of inoculation. It was noticeable, however, th it it occurred 

 only in bundles which had been ruptured by the needle used in 

 inoculation. In 1897 a 50-foot row of the same Golden Dent corn 



