NOTES ON THE POISONOUS SECRETIONS OF TWELVE SPECIES OF TOADS

In earlier reports we (1929-1931) described the isolation of the active principles from Ch’an Su and their physiological proper-ties. Ch’an Su is a well known commercial preparation, made of the dried venom of the toad, which has been used in Chinese medicine for centuries. We are now engaged in similar studies of the poisonous secretions obtained from the parotid glands of twelve different species of toads. These animals were collected from various parts of the world, and shipped to our laboratory alive so that we were able to make sure of the uniformity of the species with which we were dealing by discarding any of the toads which did not belong to that particular species. This is especially important because of the individuality of the toad poisons, as will be shown in our forthcoming papers; that is, the secretion of one species is not the same as that of another. We are greatly in-debted to Dr. Karl P. Schmidt, Field Museum of Natural His