hypophylangia (two-jointed instead of three-jointed digits) is dominant over the normal condition. In mice, the peculiar waltzing habit of so-

Fig. 6. A Guinea-pig with Short, Pigmented Coat. Its parents were the animal shown in Fig. 4 and one like that shown in Fig. 5.

Fig. 7. A Guinea-pig with Long, Smooth, Albino Coat. These three characters are all recessive in nature.

called Japanese mice is a recessive character in heredity. In man, a peculiar dark-colored condition of the urine, known as alkaptonuria, is