20 BULLETIN 69, U. S. DEPARTMENT OF AGRICULTURE. 
kidneys, and membranes of the central nervous system showed 
strong congestion. The mucous membrane of the trachea and 
bronchi was inflamed, as were also the inner walls of the small intes- 
tine and stomach and in some cases other parts of the alimentary 
canal. 
In the kidneys the congestion was most marked in the cortex and 
was accompanied with some nephritis. It was noticed that the red 
blood corpuscles in the kidneys were more or less broken down. 
Death resulted from respiratory failure. 
TOXIC DOSE. 
Very little has been known in regard to the toxic dose of Cicuta 
beyond the fact that only a small quantity is necessary to produce 
poisonous effects. 
Stockbridge, 1814, says that in a fatal case about 1 dram was 
eaten. Hedrick, 1897, states that a piece the size of a walnut was 
found by experiment to be sufficient to kill a cow. Other similar 
estimates have been made, all more or less indefinite. In cases of 
accidental poisoning it is very difficult to estimate how much has 
been eaten, and there has been little exact experimental work. 
About all that has been known is that the rootstock is extremely 
poisonous and that fatal results have followed the eating of very 
small quantities. 
The experimental work at Mount Carbon gave very little definite 
information in regard to the toxic dose. The sheep that died ate 
in two days 2.7 pounds per hundred pounds of weight. From the 
records, two other sheep which became sick apparently ate a very 
large quantity of the roots, but the circumstances of the feeding 
indicate that the actual poisoning was produced by a comparatively 
small quantity. Heifer No. 119 died as the result of eating 5 pounds 
per 1,000 pounds of weight in a single day. These deaths occurred 
at a time when, as stated elsewhere, there is reason to think that 
the Cicuta is not as poisonous as at other seasons. 
All that can be said definitely is that a very small quantity of the 
root of Cicuta may produce death, but the amount varies with 
the season and also with the period of time during which it is 
eaten. 
ANIMALS POISONED BY CICUTA. 
It is probable that most, if not all, of the higher animals may be 
poisoned by Cicuta. 
Wepfer, 1679, showed experimentally that dogs, wolves, and 
birds could be poisoned. 
Gadd, 1774, says that horses, oxen, cows, and goats are poisoned. 
