WESTERN SNEEZEWEED AS A POISONOUS PLANT. 37 
If Table 13 is taken at its face value, we must consider the plant 
as most toxic in midsummer and more toxic in September than in 
June. 
It may be seen from Table 1 that in 1918 four sheep were poisoned 
by feeding in June and July, while only one sheep, No. 469, was 
poisoned by feeding late in the season; this from August 26 to Sep- 
tember 19 received 36.058 pounds — an average daily feeding during 
25 days of 1.442 pounds. In these cases, again, the dosage of the 
latter part of the season was rather smaller than it was earlier. 
While the numbers of cases in different parts of the year are too 
small to permit of reliable averages, it seems that there is an apparent 
tendency to slightly greater toxicity in the latter part of the season. 
This probably is explained by the greater quantity of water con- 
tained by the plant early in the season. In general, it may be stated 
that there is no marked seasonal variation in toxicity. 
PERMANENT EFFECT PRODUCED BY THE POISON. 
It was noticed in the corral cases that the effect of E. Jioopesii poi- 
son was continued for a prolonged period, and that complete recov- 
ery, if it occurred at all, was slow in appearing. People who handle 
sheep in the H. Jioopesii region have a theory that a spewing sheep 
never completely recovers. It is stated that if a band of sheep is 
brought from the outside to a H. Jioopesii range, there are compar- 
atively few cases the first year, more the second, and still more the 
third. This is explained by supposing that the effects of H. Jioopesii 
feeding continue over from year to year. In connection with the 
experiments at the Salina station, some sheep were kept for two or 
more years and notes made in regard to the outcome of cases that 
were poisoned and apparently recovered. The results appear to 
show quite conclusively that the effect of H. Jioopesii poison may be 
permanent; that sheep once affected by this plant are likely to suc- 
cumb more quickly to a succeeding feeding, and, even if they appar- 
ently recover, are likely to prove worthless. 
Helenium HooPEsn a Cumulative Poison. 
As previously shown, if about 2 pounds of H. Jioopesii leaves are 
fed daily for about 20 days, sickness is produced, although a consider- 
ably smaller amount may have a toxic effect. For instance, in 1918 
Sheep 469 was made sick on a daily feeding of 1.6 pounds, while on 
the other hand 1.5 pounds was fed daily for more than 20 days with- 
out producing any effect. If less, however, than 1.5 pounds a day 
is fed, positive symptoms do not develop. For example, Sheep 467 
ate on the average of 1.3 pounds a day for 40 days without showing 
any distinctive symptoms. It will be remembered also that a single 
day's forced feeding of 2.494 pounds produced toxic symptoms. 
