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 BOTANY and vomiting. Many species of the rose family contain emulsin and amygdalin, and when the seeds are bruised these substances react and the deadly prussic acid is formed. The kernel of the sloe also contains these principles. Cattle have been poisoned by browsing on the leaves of the bird cherry, and the berries of the mountain ash have been known to cause symptoms of poisoning to children who have eaten them. Common bryony is a powerful and highly irritant purgative. The natural order Umbelliferaj affords perhaps some of the most virulent of British poisonous plants. There are found in Essex the hemlock (Conium maculatum), the water hemlock (Cicuta vtrosa), the water dropwort ((Enant6ejistu/osa),the parsley dropwort (CE. pimpinelloides), the hemlock dropwort (CE. crocatd), the fineleaved dropwort (CE. Pbellandriuni), and the fool's parsley (SEthusa Cynapiuni), all of which have caused fatal poisoning; and to these may be added the wild parsnip (Pastinaca satrva), though the cultivated plant is such a useful vegetable. Ivy has purga- tive and emetic properties, and common elder and honeysuckle are both unwholesome. The composite plants only afford us wormwood, containing an oil which is a narcotic poison, but the plant can scarcely be considered dangerous. Privet berries have certainly caused fatal poisoning, and in the root and herbage of great bindweed we have a strong emetic and purgative. The nightshade family is perhaps the most poisonous of all our orders of plants. Most if not all the plants of this order contain some one of the alkaloids known as the mydriatic alkaloids, though curiously the potatoes and tomatoes, both belonging to this order, are valuable vegetables. Potatoes are said to be poisonous when uncooked. We have in the county the following plants of this order: Bitter-sweet (Solatium Dulcamara), common nightshade (S. nigrum), deadly night- shade (Atropa Belladonna), thorn-apple (Datura Sframomium), the henbane (Hyoscyamus niger), most of which are still used in medicine. The foxglove is both very poisonous and much valued in medicine. The bark of the mezereon (Daphne Mezereum) and of the spurge laurel (D. Laureola) both afford us strong blistering agents. The spurges and perennial mercury are powerful irritant poisons. The poisonous properties of the yew are too well known : the branches in a half- faded condition are even more deadly than when fresh. It is stated that yew berries are not poisonous ; it is however wisest to leave them untasted. The wild hyacinth and herb Paris are very acrid. The meadow saffron is a narcotic irritant poison and is still used in medi- cine. The wild arum is very acrid, but the poison is destroyed by heat and the roots formerly provided a wholesome farina called Portland arrowroot, the manufacture of which was discontinued in 1853. Black bryony (Tamus communis) was formerly a favourite internal medicine, but was discontinued as it was found to be dangerous in its action. It is still used when grated as an application to blackened eyes. Common rye grass is apt to be attacked by a fungus known as ergot, 4i 6