PHYSICAL CHARACTERS IX .MAN 91 



five generations, including twent^^-seven affected 

 individuals. In six of these there was also a bifurca- 

 tion of the thumbs, which may be due to the presence 

 of a dominant modifying factor. Wegelin ( 1 9 1 7) traces 

 through three generations an abnormalit}^ affecting 

 only the little fingers. The terminal phalanx is bent to 

 the radial side, the middle phalanx shortened, and its 

 distal end oblique. It is dominant, but there were four- 

 teen abnormal to two normal in the third generation. 



The remarkable accuracy of the inheritance of 

 many digital malformations is shown incidentally by 

 a paternity case (Mohr, 1921), in which the alleged 

 father had a pronounced brachyphalangy affecting 

 the second row of phalanges on fingers and toes II, 

 III, and IV. The thumbs were normal, but the 

 basal phalanx of the great toe was shortened. The 

 hands and feet of the child showed exactly the same 

 malformation, and radiographs indicated absolute 

 correspondence in the bones. The man was there- 

 fore adjudged to be the father. 



There is an early record* of a peculiar form of 

 brach3"dact\dy in which the mother and two children, 

 who were examined at Uxbridge, had normal thumbs, 

 but the fingers had only one phalanx each, except the 

 ring finger of the left hand, which had two phalanges. 

 There w^ere no nails on these fingers. All the rest 

 of the family were said to be the same, and the con- 

 dition was stated to have been inherited for nine 

 previous generations, but there are no records to 

 substantiate these statements. The character was 

 only transmitted by the w^omen, who sometimes had 

 a child wdth perfect fingers. 



In another case (Rieder, 1899) the father had a 



rudimentary (short) fourth metacarpal bone, the 



ring finger being also short and small. The daughter 



exhibited " lobster claw " in the right hand, while 



* Edin. Med. and Surg. Journ., 1808, iv., 252. 



