An interesting example of the importance of making a proper choice of animal parts in order to make a complete diet, is afforded by the experience of those who have attempted to rear young lions in captivity. With few exceptions in the past such attempts have proven failures, since the animals developed rickets. If they survived they were so deformed as to be unfit for exhibition purposes. In recent years in at least two zoological gardens these animals are now reared successfully. A young lion cannot grow normally on a piece of muscle meat with a large, hard bone attached. In many cases the large bones given them were so hard that little could be gnawed therefrom. When these animals are fed with liver, fat, and bone of a type which they can eat in considerable amount without danger of choking, and when their diet is varied frequently with small animals which can be consumed entirely, such as rabbits or pigeons, they grow up strong and beautiful.