Solanum tuberosum.—The small, immature tubers of the common cultivated potato and those that have turned green from exposure to the sun are slightly poisonous. The green fruit and the white sprouts from mature potatoes are likewise poisonous. In all of these cases the deleterious substance may be removed or destroyed by thorough boiling.
SCROPHULARIACEÆ (FIGWORT FAMILY).
Fig. 113.—Sneezeweed (Helenium autumnale), one-third natural size.
Digitalis purpurea.—The purple foxglove is a common garden plant which has sparingly escaped from cultivation and is naturalised to some extent on Cape Breton Island. Horses are occasionally poisoned in Europe by nipping the plants from gardens or by eating hay contaminated with it.
Gerardia tenuifolia.—The slender gerardia is native to the eastern half of the United States, and has been specially reported as poisonous to sheep and to calves in the Southern States.
Gratiola officinalis.—The hedge hyssop of the Southern States contains an acrid poison. The same plant grows in Europe, and is there regarded as poisonous to stock.
Pedicularis.—The plants of this genus are commonly called lousewort. In Europe several species are suspected of being slightly poisonous to stock. One of these, P. palustris, occurs in Labrador, and there are over thirty species native to the United States, largely Western. They should all be suspected of being poisonous.
CAMPANULACEÆ (BELL-FLOWER FAMILY).
Lobelia inflata, Indian tobacco: L. kalmii, brook lobelia: L. spicata, pale-spiked lobelia: L. syphilitica, great lobelia.—All of the species in this genus contain an acrid and usually milky juice, and are poisonous. None has been specially reported as poisonous to stock, but the above-named species are to be suspected, because they frequently occur in grass and are sometimes found in meadow hay.