HOT WATEE STEEPING OF SEED-CORN. 35 



By treating the grain with 0-5 per cent of bkie vitriol he obtained 

 86i- per cent of plants. It may therefore be inferred that an immersion 

 of five minutes suffices, and that it has an advantage over blue vitriol 

 because it stimulates germination instead of retarding it like the latter. 

 Klebahn, however, is of opinion that immersion has no advantage over 

 vitriol steeping, and Kirchner asserts that it diminishes the germinative 

 power. Selby found that the same result was got by immersion as by 

 treatment for twenty-four hours with a solution of 0-5 per cent of blue 

 vitriol, 0'2 per cent of formaline, and 0"75 per cent of potassium 

 sulphide. When wheat is immersed on the large scale against bunt it 

 is well to dip the grain first in water, skim it, and cast aside all those 

 grains which float. These are precisely the bunt-infested ones. Those 

 which lie on the bottom of the water are alone dipped in the hot water. 

 Ustilago Avenae, Eost. (loose smut of oats, A vena sativa) ; Ustiiago 

 jmrennans, Eost. (smut of oats. Arena elatior). — The spores of Usti- 

 lago Avenae stand air heated to 52° C. (125-6" F.), but they do not 

 stand dipping in hot water at 54°-56° C. (i29-2°-132-8° F.) (Sorauer). 

 Kirchner found that seed-oats treated in that way gave the following 

 result against untr( 



TABLE NIL—Shoioijig Effect of Steeping Seed-Oats in Hot Water on Germin- 

 ative Capacity. 



Germinated Germinated 



in two days. in ten aayi--. 



Per cent. P(r cent. 



Treated .... 24-75 84-5 



Untreated .... 6-75 81-75 



Treatment on the large scale lowers the percentage of diseased plants'- 

 to about 0'2-0-7 per cent (Eriksson). According to Kellermann and 

 Swingle, a fifteen minutes' dip in water at 55'6° C. does not alter the 

 germinative power of oats, and all authors agree in saying that the- 

 immersion of seed-oats is better than treatment with blue vitriol, because 

 it stimulates instead of retards the germination. It is therefore from 

 thib point of view a useful discovery, and Klebahn is of opinion that 

 this treatment, general for all other cereals, is prescribed for oats. 



Uroctjstes occulta, Eabenh. (smut of the stems of rye). — By im- 

 mersing seed-rye for five minutes in hot water Kirchner obtained 

 against untreated grain the following results : — 



TABLE VIII. — Showing Effect of Steeping Seed-Rye in Hot Water on Germin- 

 ative Capacity. 



Treated 

 Untreated . 



Trials on a large scale by Klebahn did not give better results. The 

 immersion of seed-rye presents no advantage in this case over treat- 

 ment with blue vitriol, because it retards germination like the latter. 

 Ustilago Panici-Miliacei, Wint. (smut of millet). — Treatment with 



