26 BULLETIN 947, U. S. DEPARTMENT OF AGRICULTURE. 
herders. It is not unusual, when a flock of sheep has been feeding 
upon a H. hoopesii area, to see large numbers of them throwing up 
their heads and vomiting. The large sheep in the foreground of 
figure 3, Plate II, shows the typical attitude of one of these animals 
in a flock feeding upon the range, and figure 4 of Plate I shows the 
attitude assumed by a corral force-fed animal in the act of vomiting. 
Sheep 420, which became ill from prolonged feeding, is shown in 
Plate II, figure 4, in an attitude produced by nausea. The pictures 
of Cattle 827 (PL II, figs. 5 and 6) show nausea and vomiting. 
This tendency to vomit may continue for a prolonged period after 
the feeding upon E. hoopesii has been stopped. The experiences 
with the animals in 1917 may be quoted as giving a definite idea of 
the frequency of this symptom. Out of 12 prolonged feedings and 
2 repeated forced-feeding cases in this year vomiting occurred in 
8 feedings and in 1 of the repeated forced-feeding cases. Of the 8 
acute cases in this year only 1 showed a tendency toward vomiting. 
Coughing. — Many of the poisoned sheep were noticed to be fre- 
quently coughing. This was particularly noticeable in the animals 
poisoned upon the range. It is probably due to mechanical irrita- 
tion caused by material from the stomach getting into the larynx. 
Bloating. — Bloat occurred in some of the experimental animals in 
both acute and chronic cases, and when it occurred was sometimes 
accompanied with the belching of gas from the stomach. Bloating 
can not be considered as a usual symptom of the experimental ani- 
mals. In range cases, however, most of the spewing cases apparently 
are bloated. 
Trembling. — Trembling was noticed in a number of the cases, but 
can hardly be considered a characteristic symptom, as it probably 
results simply from the general weakness of the animal. 
Diarrhea. — In some of the animals diarrhea followed the severe 
stages of the sickness and was noticeable before complete recovery 
took place. It was not, however, a usual symptom, and neither it 
nor constipation can be considered as characteristic of H. hoopesii 
poisoning. 
Most Prominent Symptoms. 
The especially prominent symptoms, then, of H. hoopesii poisoning 
are general depression, weak and irregular pulse, weakness, and 
nausea, followed by more or less chronic vomiting. Vomiting is not 
a characteristic of the acute cases and does not always appear in the 
chronic cases. Apparently the chronic cases of sheep can be divided 
into two types — one characterized by extreme weakness with rapid 
and irregular pulse, and the other with the added symptom of 
vomiting. 
Death comes on quietly and is not accompanied by convulsions. 
Plate I, figure 6, shows Sheep 314 in the last stages. 
