POISONING BY ST. JOHN’S WORT.
The ingestion of St. John’s wort produces excitement followed by dulness, interference with vision and hearing, and by visual hallucinations with a tendency to lean backwards, the front limbs remaining fixed in position. The patient often sits down on the hind quarters like a dog.
APIACEÆ (CARROT FAMILY).
* Cicuta maculata. This is the water hemlock (spotted hemlock; beaver poison; cowbane), which grows most abundantly throughout the United States. It is one of the best known poisonous plants. Stock are not infrequently killed by eating the fleshy roots or hay with which the plants are mixed.
Fig. 101.—Oregon water hemlock (Cicuta vagans). a, Plant with leaves, one-sixth natural size; b and b′, rootstock and horizontal roots, showing section, half-size; c, terminal leaflets, one-sixth natural size; d, flowering spray, full size.
Fig. 102.—Poison hemlock (Conium maculatum), showing upper portion of plant with flowers and seed, one-third natural size.
* Cicuta vagans.—Cattle are frequently killed in Oregon and Washington by eating the large fleshy rootstocks which have been washed, frozen, or dug out of the soil, or by drinking water in marshes where the roots have been trampled upon. The roots of the other species of Cicuta are undoubtedly poisonous, but cases have been reported against one other species only, namely, C. bolanderi. It grows in marshy land in California.
* Conium maculatum.—The well-known poison hemlock, or spotted hemlock of Europe, is an introduced weed not uncommon in the north-eastern section of the United States and in California. The plant is generally avoided by stock on account of its bad odour, but animals have been killed by eating it in the fresh state. Since the poisonous constituent is volatile, the dry plants are not so dangerous.