638 



treated with sulpbate of copper or left untreated, It was also found 

 that the seeds treated with hot water germinated more rapidly than 

 the untreated seeds " whatever the length of time that had intervened 

 between the treatment and the germinating test, even up to nine 

 months." In experiments with sulphate of copper it was observed 

 that tbe plumules started out earlier than the rootlets. This was due 

 to the fact that " the primary roots were killed before starting and the 

 secondary ones, which took their places, were consequently late in 

 appearing. This action of the co^jper sulphate in killing the primary 

 roots and retarding germination has been known for some time, although 

 but few observations have been recorded." 



Kansas Station, Bulletin No. 15, Decemher, 1890 (pp. 43). 



Additional experiments and observations on oat smut, 

 MADE IN 1890, W. A. Kellerman, Ph. D., and W. T. Swingle, B. S. 

 (pp. 93-133, illustrated). — Previous accounts of statistics and experi- 

 ments on oat smut {Ustilago avouv) may be found in Bulletin No. 8 and 

 the Annual Keport of the station for 1889 (See Experiment Station 

 Kecord, Vol. I, p. 216, and Vol. II, j). 342). A similar report on exi)eri- 

 ments with fungicides for stinking smut of wheat {Tilletia foetens and 

 T. tritici) was published in Bulletin No. 12 of the station (See Experi- 

 ment Station Eecord, Vol. II, p. 220). In the present bulletin are 

 observations as to the amount of oat smut, an account of experiments in 

 preventing the smut in 1890, brief statements regarding hidden smut, 

 a discussion of the increase in yield caused by the Jensen hot-water 

 treatment of the seed, and full directions for treating the seed to pre- 

 vent the smut. 



Amount of smut (pp. 94-100). — Tabulated data are given for counts 

 of the amount of smut in fields at Manhattan and elsewhere in Kansas, 

 and in plats on the station farm, where " two hundred single plants of 

 each of 80 varieties of oats were planted, each plant having a space of 

 64 square inches." The twenty field counts reported show an average 

 of 6.46 per cent of smut in 1890, " an amount considerably smaller than 

 that obtained for 1888 and 1889." The amount of smut in the plats 

 varied very greatly, ranging from to 50 per cent. Seventeen varieties 

 had over 11 per cent of smut. Counts of the smutted heads were also 

 made on 15 plats planted with "light, common, and heavy seed," as 

 explained in Bulletin No. 13 of the station (See Experiment Station 

 Eecord, Vol. II, p. 223). The results, as tabulated, show that " the 

 common seed gave the largest per cent (13.25) of smut, the light seed 

 the least (9.23), while the heavy seed gave a percentage about midway 

 between the other two (10.78). 



Ridden smut (pp. 100-102). — In the case of a few varieties of oats it 

 was found that " many heads having nearly or quite the normal appear- 

 ance were nevertheless smutted." Heads of oats affected in this way 

 are illustrated in a plate. 



