A fish is a cold-blooded animal; that is, his temperature is nearly the same as that of the water in which he lives. His circulation is sluggish and his appetite is a variable quantity. He has the capacity to take in large quantities of food at one meal and properly assimilate it; on the other hand he is able to fast for weeks at a time. He has his own notions about eating, and it is quite impossible to induce him to change them, and all this has considerable influence on his rate of growth. It is out of the question to expect him to grow when he is fasting; on the other hand he must draw on the fat he has stored up in his body to furnish him energy for his muscular movements and to carry on the ordinary functions of nutrition. The fish here has an advantage over the warm-blooded animals, for he does not need to generate heat to keep his body at a constant temperature. The amount of food often eaten at one time is quite remarkable. I remember once of taking nearly one pound of sunfish from the stomach of a Large-mouthed Black Bass. This does not indicate that a bass must eat such meals three times each day, it only shows his capacity to make use of a large quantity of food when it is abundant and his stomach feels the need of it. A trout is a good feeder; his stomach and mouth are large, much in size like that of the black bass. From experiments conducted at Neosho, Missouri, by Mr. Page, he found that a young trout did best on a daily ration of solid food equal to about seventy-five per cent of its weight. On this amount the trout would reach an average length of six inches in one year. The average amount of solid food consumed daily by a man is from one and one-half to two per cent of his weight, or more than twice that consumed by our active, growing young trout. As mentioned before, the trout is relieved from generating heat to keep his body at a constant temperature, and at one usually much higher than the medium in which he lives.