PHYSICAL CHARACTERS IN MAN 83 



but the middle phalanx of each finger is abnormally 

 short. This is partly due to the absence of the 

 epiphysis from the base of the second phalanx, 

 except in the thumb and middle finger, and also to 

 a slight shortening of the second phalanx, but is 

 chiefly due to the fact that the cartilage between the 

 shaft and the epiphysis becomes prematurely ossified, 

 thus causing cessation of growth in length of the 

 fingers at an early age. Ankylosis of the epiphysis 

 and the second phalanx frequently occurs earlier in 

 the first and fourth fingers than in the second and 

 third, thus leading to a greater shortening of the 

 former. The abnormality of the toes is practically 

 identical with that in ordinary brachydactyly. This 

 family is also shorter in stature. As in the brachy- 

 dactylous family, the women are 4I inches and the 

 men 8 inches shorter than their normal siblings. A 

 total of twenty-one abnormals to twenty-six normals 

 were recorded in families having one abnormal 

 parent. The abnormals in this family are said to 

 have better health than the normals. In the children 

 the abnormality is inconspicuous, and is sometimes 

 detected only by flexing the finger. 



In the second family showing minor-brachydactyly 

 (Drinkwater, 191 4), the conditions closely resemble 

 those in the previous family, but so far as the records 

 go back there is no connection. It is found in five 

 generations, there being nine abnormals to ten 

 normals, eight of the former now living. They are 

 all descended from an illegitimate daughter of a short- 

 fingered man, the mother having been married to a 

 normal man by whom she had entirely normal descen- 

 dants . These forms of brachydactyly are, therefore, all 

 simple Mendelian dominants like split-foot, but they 

 show no appreciable excess of abnormals in inheritance, 

 and they show a clear tendency to increase rather 

 than die out, notwithstanding their social handicap. 



