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IOWA ACADEMY OF SCIENCE 
127. Sisymbrium altissimum, L. Tumbling Mustard. 
Weed common in grain fields in the north and may thus find its way into 
wheat screenings. Such screenings should be fed with caution. Probably pro- 
duces sinapism, as the other plants of the order. It is also found in this state. 
128. Brassica sinapistrum, Boiss. Charlock. 
This weed produces sinapism. After the application of the powdered ma- 
terial, there is a sense of burning. The volatile oil of mustard is a powerful 
irritant, and caustic, and should be used with caution. 
SARRACENIALES. Sarraceniaceae. 
129. Sarracenia purpurea, L. Side-Saddle Flower. 
Probably not native to the state, although it is found distributed with 
Drosera in LaCrosse County, Wisconsin, and formerly also in Houston County, 
Minnesota. The plant contains the substance sarracenin. The root produces 
diuresis, gastric excitation, and an increased, irregular action of the heart. 
It produces papular eruptions changing to vesicular with depression as in small- 
pox. The plant was formerly used medicinally by the Indians. 
Droseraceae. 
130. Drosera rotundifolia, L. Sundew. 
Sundew is said to be poisonous to cattle. It is not known to be native to 
the state, although it occurs in Western Wisconsin, north of the Iowa line, 
and also in Houston County, Minn. 
ROSALES. Saxifragaceae. 
131. Sedum acre, L. Stone Crop. 
Produces inflammation when applied to the skin of many persons. The 
juice is acrid and biting. 
Rosaceae. 
132. Fragaria vesca, L. European Strawberry. 
Found on sand-stone and limestone rocks. Produces irritation of the 
stomach in some people. 
133. Fragaria virginiana, Mill. Wild Virginia Strawberry. 
Similar to the preceding. 
134. Fragaria chiloensis, Duchesne. Cultivated Strawberry. 
Like the preceding. I have known people who could not eat strawberries 
or pick them without being irritated. 
135. Rosa arkansana, Porter. Arkansas Rose. 
Widely distributed in the state, especially prairie regions. Not poisonous, 
but the bristles and prickles often enter the skin and produce serious inflam- 
mation. 
136. Rosa rubiginosa, L. Sweetbriar. 
A frequent escape in pastures. The recurved spines and prickles are 
injurious like the preceding species. 
137. Pyrus aucuparia, Meyer. Mountain Ash. 
The berries are poisonous to man, but not to birds. However, fhey are 
readily disseminated by birds. 
138. Pyrus communis, L. Pear. 
Dr. Schaffner states that horses are reported to have been killed by eating 
rotten pears. 
