This name, which is derived from a Persian word implying an antidote to poison, was given to a concretion found in the stomach of an animal of the goat kind, and once very highly valued for this imaginary quality; and hence it has been extended to all concretions found in the intestines of animals. Of these there are several kinds; first, superphosphate of lime, which forms concretions in the intestines of many mammalia; secondly, phosphate of ammonia and magnesia, a concretion of a gray or brown colour, composed of radiations from a centre, and found in the intestines of herbivorous animals, such as the elephant, the horse, &c.; thirdly, biliary concretions, of a reddish brown colour, and frequently met with in the intestines and gall bladders of oxen. This kind is composed of inspissated bile, and is used by painters as an orange-yellow pigment. Besides the above, they also occur hairy, resinous, and ligniform.