U. S. DEPARTMENT OF AGRICULTURE. 
more extended, as shown in Plate II, which is reproduced from a 
photograph of a Montana plant. Plate III shows the plant after 
the seed is formed. 
COMMON NAMES OF ZYGADENUS. 
The species of Zygadenus are known under a large number of pop- 
ular names. The most common perhaps is death camas. In the 
Northwest perhaps lobelia is the name used even more generally than 
death camas. Other names are soap plant, alkali grass, water lily, 
squirrel food, wild onion, poison sego, poison sego lily, mystery grass, 
and hog's-potato. Z. glaberrimus is said to be called cow-grass. 
POISONOUS SPECIES OF ZYGADENUS. 
The following species of Zygadenus are said to be poisonous: Z. 
elegam, Z. falcatus, Z. fremontii, Z. glaberrimus, Z. intermedins, Z. 
mexicanus, Z. nuttaTlii, Z. paniculatus, Z. venenosus. 
This list is given in accordance with the statements of various 
authors, and no attempt has been made to revise it from the stand- 
point of the systematic botanist. Apparently all species of this genus 
may be presumed to be poisonous. Even Zygadenus coloradensis, 
which has been shown not to be injurious to stock in Colorado, has 
the same poisonous principle as the other species, but in smaller 
quantity. 
LOSSES OF LIVE STOCK BY ZYGADENUS. 
As already stated, there is reason to think that deaths of cattle and 
horses from Zygadenus poisoning are not numerous. With sheep, 
however, the losses are very heavy, but it is impossible to make even 
an approximate estimate of these losses. It is probable that they 
are much greater than is generally supposed, for in the sheep-grazing 
regions many, perhaps most, of the herders do not know the plant and 
consequently do not recognize it as the cause of illness and death in 
the bands under their charge. The lupines, without any doubt, have 
been blamed for many of the cases of poisoning by Zygadenus. 
Chesnut and Wilcox (1901, p. 53) state that 636 sheep died from 
Zygadenus poisoning in Montana in 1900 and that 3,030 were poisoned. 
In one locality in Wyoming 500 sheep died out of a total of 1,700 
poisoned, and in one county it was said that 20,000 died in 1909. The 
writers of this paper investigated a case in Montana in which 500 sheep 
died within a few hours, the probable cause being Zygadenus. 
There is no doubt that this plant is one of the sources of heaviest 
loss to sheep owners, especially in Wyoming and Montana. There is 
good reason, too, for thinking that many of the losses in Oregon, 
Utah, and California which have been ascribed to other plants were 
really caused by Zygadenus. 
