and, as far as is known, grown cattle are only slightly or not at all affected by the poison. Calves, swine, horses, and especially dogs, are more or less susceptible. Concerning birds and fowls there is some doubt.” Though animals are reputed to become tolerant of the poison if the cockle is only taken in small regular doses, yet there appears to be a chronic form of poisoning due to this cause and termed _Githagism_, while there is an acute poisoning due to the ingestion of large quantities of the seeds which may cause death in 24 hours or less. It is clear that the evidence is quite sufficient to warrant the statement that the ingestion of more than a very small quantity of cockle seed is dangerous, and the consumption of even small quantities should be avoided. Thus care should be taken to remove the seeds from cereal grains. _Toxic Principle._ The dangerous substance contained in cockle seeds is the glucoside variously known as _Githagin_, _Saponin_, _Agrostemmin_, _Sapotoxin_, _Agrostemma-Sapotoxin_, or _Smilacin_ (C_{17}H_{26}O_{10})_{2}. This principle appears to occur chiefly in the seeds, which contain up to 6·56 per cent., but it has been found in small quantities in other parts of the plant. It is very freely soluble in water, in which it froths like soap when shaken up, and it has a sharp taste and no odour. _Symptoms._ A sufficient quantity of the toxic substance may cause nervous debility and dysentery—according to Chesnut “intense irritation of the digestive tract, vomiting, headache, nausea, vertigo, diarrhœa, hot skin, sharp pains in the spine, difficult locomotion, and depressed breathing. Coma is sometimes present and may be followed by death. In animals chronic diarrhœa and gradual depression.” The chronic form, which occurs when small doses are repeated over a long period (practically the only form found in human beings, but never in animals, except perhaps in the pig) is characterized by gradual wasting away, loss of breath, loss of strength, chronic diarrhœa, and nerve troubles, death taking place in marasmus and decline. The active principle acts as an irritant on the digestive tract, causing colic, diarrhœa and enterorrhagia. Cornevin describes the symptoms in the acute form of the poisoning in the case of horses, cattle, pigs and dogs. In the _horse_, if a small quantity only is taken, there is yawning, heavy colic, stamping and evacuation of rather soft fæces. If larger quantities are taken, the symptoms, which commence in about an hour, are salivation, frequent yawning and turning of the head, colic, pale mucus, hurried and weak pulse, rise in temperature and accelerated respiration. Some time later there are muscular tremors succeeded by pronounced rigidity, and the fæces are diarrhœic and fœtid. The animal lies down, and getting up is painful; it falls into a kind of coma, stretches itself to the utmost, and death takes place without convulsions.