WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock. Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.