IOWA ACADEMY OF SCIENCE 
163 
longed boiling, however, extracts the greater part of it, but it is not destroyed, 
consequently this water should not be used, as it contains the substance 
which is converted into hydrocyanic acid. 
GERANIALES. Oxalidaceae. 
162. Oxalis violacea, L. Wood Sorrel. 
Dr. Schaffner reports a case of a boy who was poisoned from eating a con- 
siderable quantity of the leaves. The leaves are frequently eaten. 
Linaceae. 
163. Linum usitatissimum, L. Flax. 
Said to produce death to cattle, probably due to the formation of hydro- 
cyanic acid in the wilted leaves. People working with the fiber of the plant 
often have a form of dermatitis. The Flax-seed, when fed in considerable 
quantities to live stock, especially hogs, produces death. The Linum cathart- 
icum contains a bitter principle linin, and linamarin. 
164. Linum rigidum, Pursh. Large-flowered Yellow Flax. 
This plant is reported as poisonous to sheep in some parts of the country. 
Found in the western part of the State. 
SlMARUBACEAE. 
165. Ailanthus glandulosa, Desf. Tree-of-Heaven. 
This plant is occasionally spontaneous in the southeastern part of the State, 
where it is cultivated as an ornamental plant. It is supposed to produce poi- 
soning when people come in contact with it. The odor of the flowers is very 
disagreeable. It is said also, according to Dr. Rusby, that the water coming 
in contact with the leaves is poisonous. 
POLYGALACEAE. 
166. Polygala senega, L. Seneca Snakeroot. 
The roots of this plant are used in medicine as an emetic. The plant is 
common in the Eastern part of the state. 
Euphorbiaceae. 
167. Croton capitatus, Michx. Hogwort, Croton. 
Native to Southeastern Iowa. Many species of the genus contain very 
active poisonous principles. While this plant has not been suspected, the 
related species, C. texensis , is known to be poisonous. 
168. Ricinus communis, L. Castor-Oil Plant. 
Widely cultivated as an ornamental plant. The seeds contain a deadly poi- 
sonous substance ricin. 
169. Euphorbia corollata, L. Flowering Spurge. 
Widely distributed in the state, upon sandy or gravelly soil. Produces in- 
flammation of the skin. 
170. Euphorbia preslii, Guss. Spurge. 
Widely distributed in meadows and fields. It has been sent to the writer 
as supposedly poisonous to live stock. 
171. Euphorbia marginata, Pursh. Snow-on-the-Mountain. 
The honey coming from the plant is poisonous. The milky juice produces 
dermatitis. At one time the plant was used for branding cattle. 
172. Euphorbia lathyris, L. Caper or Myrtle Spurge. 
