Fig. 17.—At the left is a hand with the third, fourth and fifth fingers affected. The middle joints of these fingers are stiff and cannot be bent. At the right the same hand is shown, closed. A normal hand in the middle serves to illustrate by contrast the nature of the abnormality, which appears in every generation of several large families. It is also called symphalangism, and is evidently related to the better-known abnormality of brachydactyly. Photograph from Frederick N. Duncan.
