=White-Rot= or =Marsh Penny-Wort= (_Hydrocotyle vulgaris_ L.) is stated to have caused inflammation of the digestive tract, and hæmaturia; and to contain a toxic substance _Vellarin_ (213). =Wild Parsnip= (_Pastinaca sativa_ L.). This plant has often been supposed to be poisonous, but Pammel shows that in Iowa the plant is quite harmless, as it appears to be in Britain. =Devil’s-Bit= (_Scabiosa succisa_ L.) is stated by Moir to have caused injury to cattle in one instance (_Vet. Record_, 1899), causing salivation, gritting of the teeth, twitching of facial muscles, and slightly protruded, abraded, swollen and sensitive tongue. An experiment on cattle showed the plant to induce violent inflammation of the mouth and tongue. =All-Heal= (_Valeriana officinalis_ L.) is not likely to be eaten by stock in sufficient quantity to cause poisonous symptoms, though it is stated to contain the poisonous _Valerianic acid_ and _Oil of Valerian_. According to Chevalier (_vide_ Henry) this plant contains an alkaloid not yet fully characterised. =Canadian Erigeron= (_Erigeron canadensis_ L.), sporadic in England, is suspected in America. It contains an oil, chiefly a _terpene_ (C_{10}H_{16}). It has an acrid taste, causes smarting of the eyes, soreness of throat, aching of extremities, and colic; and irritation to people handling it (203). =Mayweeds= (_Anthemis_ sp.). It is not at all clear whether these plants are more than irritant in character, and they are so very common and widely distributed that there would probably be more evidence if they were poisonous. _A. Cotula_ is regarded as suspected by Smith and Halsted, while Ewart says that it is obnoxious to stock on account of its unpleasant flavour, and if eaten by them in time of scarcity is apt to give their flesh, milk, or butter an unpleasant flavour. Güssow states that this species blisters the mouth and nostrils of animals. In his investigations at Kew, Greshoff found that the seeds of _A. Cotula_ and _A. arvensis_ contain much hydrocyanic acid. (He further found that the cyanogenetic glucoside from _A. aetnensis_ Schouw. and _A. chia_ L. belongs to the amygdalin type, giving off hydrocyanic acid and benzaldehyde on hydrolysis. “The strong odour of benzaldehyde may even be observed on grinding the seeds with water. Species of _Anthemis_ contained from 0·15 down to 0·03 per cent. of hydrocyanic acid.”) =Cat’s-Ear= (_Hypochæris radicata_ L.). No record of poisoning of Cat’s Ear has been found, but it may be mentioned here, since Ewart says of it: “It contains a bitter, milky sap, which makes it unpalatable though not entirely poisonous.... An exclusive diet of this weed could not help but injure stock eventually.”