_Inhaled_ it produces intoxication, excitement, general anæsthesia and finally collapse. In rabbits it causes intense excitement, giddiness, swaying from side to side, and reckless leaps forward, followed by profound sleep with deep stertor, and paraplegia for half an hour after the return of consciousness (Oliver). When taken for a long time in smaller quantity it caused weakness, emaciation, tremors, paraplegia, and death in convulsions. There was polyuria, with excess of sugar but neither urea nor albumin. The large cells in the motor areas of the brain, when stained by Golgi’s method, showed the axis cylinder distorted and varicose, and the cytoplasm stained unequally. The action on dogs was essentially the same, and in neither animal were changes in the blood globules observed (Oliver). In man slow poisoning caused headache and exhilarate intoxication, followed by depression, mental apathy, dullness, loss of memory, impaired vision, hearing, sexual desire and muscular power. Cramps are common (Delpech, Curtis). _Treatment_ consists in giving pure air, good food, massage, galvanism, tonics, and for the persistent nervous failure phosphorus. TETANY. Definition. Casual and experimental cases in animals. Causes: Excision of the thyroid, indigestions with fermentation, rheumatism, infection, malaria, rachitis, want of hygiene, hereditary or developmental irritability, microbian poisons. Symptoms: intermittent spasms with semi-flexed limbs, tremors. Diagnosis: by the complete intermissions of spasms, and by pressure on nerve or artery, rousing them. No fever. Like spasms of ergot. Treatment: thyroid extract, grafting thyroid; remove sources of irritation, antispasmodics, warm or tepid baths, electricity. _Definition._ Tetany is the name given to a limited contraction of a group of muscles usually in the extremities occurring paroxysmally with intervals, during which it may usually be roused into activity by compression of the nerve or artery proceeding to the muscles in question. The disease has not been accorded a place in systematic works on veterinary medicine, though cases have been recorded which are supposed to have been of this nature, and in cases occurring in man and associated with dyspepsia and gastric dilation, Bouveret and Devic have extracted from the contents of the stomach a toxic substance which caused tetanic convulsions in animals. The total removal of the thyroid gland, or even of four-fifths of it (Eiselsberg), in the cat is found to be invariably followed by tetany.