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IOWA ACADEMY OF SCIENCE 
265. Rudbeckia laciniata, L. Cone-flower. 
In moist grounds throughout the state. Dr. Schaffner says it is supposed 
to be poisonous to sheep. 
266. Bidens frondosa, L. Black Beggar-ticks. 
Common in the state. The downwardly barbed awns are irritating. 
267. Coreopsis discoidea, T. & G. Small Beggar-ticks. 
Very common in the state. Is a local irritant. 
268. Helenium autumnale, L. Sneezeweed. 
Common in low grounds throughout the state. Used by the Indians to pro- 
duce sneezing. The whole plant and flowers are poisonous to cattle and sheep. 
269. Achillea millefolium, L. Yarrow. 
Used as a forage plant, but it causes an irritating sensation of the mem- 
branes and much pain in the gastric and abdominal regions. It contains the 
glucoside achillein C 2 H 38 N 2 O 15 , an amorphous bitter substance, the alkaloid 
moschatine C21H27NO7. 
270. Anthemis cotula, L. Mayweed. 
Has a very disagreeable odor, causes blistering of the skin. The plant is 
carefully avoided by stock. 
271. Dysodia chrysanthemoides, Lag. Fetid Marigold. 
Common in the western part of the state. The leaf bracts and other 
parts of the plant are provided with large pellucid glands which produce 
the characteristic odor of the plant. 
272. Tanacetum vulgare, L. Common Tansy. 
Introduced into many parts of the state. Many serious and a few fatal 
cases of poisoning are recorded by the use of tansy oil. The symptoms of 
poisoning are varied, convulsions, violent spasms, dilation of the pupils, fre- 
quent and feeble pulse. Eleven drachms of the oil in a girl produced death 
in three and one-half hours. The effect on animals is salivation, vomiting, 
dilation of the pupils, muscular twitchings, followed by chronic spasms, death 
appears to be caused by paralysis of the heart and lungs. 
273. Artemisia biennis, Willd. Biennial Wormwood. 
Probably poisonous. 
274. Artemisia absinthium, L. Common Wormwood. 
Occasionally cultivated. The volatile oil of the plant is a violent, narcotic 
poison. Contains the glucoside absynthiin C 15 H 20 O 4 , the alkaloid abrotine 
C 21 H 22 N 2 O 2 , the bitter principle santonin Ci 5 Hi 8 0 3 . 
275. Arctium lappa, L. Burdock. 
Produces itching. Contains the alkaloid lappine. Common weed in the 
state. 
