THE WHOKLED MILKWEED AS A POISONOUS PLANT. 5 
A considerable quantity of the plant was collected and sent to the 
Salina experiment station, where experiments, which were imme- 
diatel} T undertaken, proved it to be extremely toxic. 
Assistant Botanist Eggleston spent most of July, August, and 
September, 1918, in investigating the distribution and habits of the 
whorled milkweed in Colorado, Utah, and New Mexico. 
DESCRIPTION OF ASCLEPIAS GALIOIDES. 
Asclepias galioides, whorled milkweed. The stems are erect, sin- 
gle, or several, sometimes branching, "near woody 55 at base, and from 
1 to 5 feet high ; the main roots are horizontal, often branching, with 
adventitious buds producing new stems ; the leaves are in whorls, from 
2 to 6, narrowly linear, from 2 to 4 inches long ; the flowers are in um- 
bels from one-half to 1 inch across, at the ends of branches or in the 
axils of leaves; the 5 greenish- white sepals are ovate, refiexed, and 
persistent; the petals are united; there is a crown of cornucopialike 
segments with horns attached between the corolla and stamens; the 
stamens are 5 in number, and the pollen coheres in a waxy mass 
which is removed bodily by insects ; the pods are from 1 to 3 inches 
long, narrow, hairy, splitting on the sides ; the seeds are flat, reddish- 
brown, with a tuft of long, silky hairs at summit. It flowers in June 
and July, the blooms often continuing until September. 
Plate I illustrates the mature plant, showing both flowers and fruit. 
Plate II shows also the root, and Plate III shows the extended root 
system of even small plants. Plate IV, figure 1, shows the plant 
growing in an abandoned orchard. 
There seems to have been some confusion in regard to the sys- 
tematic position of the whorled milkweed. Glover, 1917, and Glover, 
Newsom, and Bobbins, 1918, call it A. verticillata. The plant col- 
lected in southern Utah, as stated on page 3, was known as A. suhu- 
lata. A special study of the subject was made by Mr. Eggleston with 
the following result : 
The whorled milkweeds were named by Dr. Gray, 1886, as follows : 
Asclepias mexicana. 
Asclepias verticillata. 
var. siibverticillata. 
var. pumila. 
A. galioides was first described by Humboldt, Bonpland, and 
Kunth, 1818, from the State of Michoacan, Mexico. 
Miss Anna M. Vail, 1898, separated the group into 7 species. 
Wooton and Standley, 1915, considered A. galioides the common 
New Mexico species of whorled milkweed and then reached the fol- 
lowing conclusions in regard to other species : 
Our specimens may include A. verticillata, but we have been unable to sepa- 
rate them definitely. They also include specimens cited by various authors as 
