FAMILY RECORD. 36 



1155.2 a 9 R. S. H. and 1155.2 b 9 I. J. H. are identical twins (b. 

 Sept. 19, 1915). Genetically these two individuals are to be regarded 

 as identical, a view that is supported in an interesting way by the fact 

 that they both have brachyphalangous indices of exactly the same 

 type. The photographs (figs. 16 and 17) showing their hands had 

 to be taken under very unfavorable conditions, but still show the 

 brachyphalangy fairly well. 



It has not been possible to take radiographs of the children, because 

 they live in a distant community and nothing absolutely certain can 

 therefore be said concerning the type of the malformation; but the 

 fact that the photographs, which were taken when the children were 

 a little more than two years old, already show a very marked shorten- 

 ing of the indices makes it exceedingly probable that the shortening 

 later will prove to be of the B !-type. 



Genetically the two children are heterozygous for the factor for 

 brachyphalangy. 



Summing up, we find that the B-type brachyphalangous 115.5 cf 

 had one child concerning whom no information is obtainable and two 

 brachyphalangous twins, probably of the B !-type. These two indi- 

 viduals have developed from one egg. When we later work out the 

 numerical ratio between brachyphalangous and normal members of 

 the famines here studied, they will have to be counted as one individual. 



Eighth Family of V Generation. 



The B!-type brachyphalangous 115.6 cf C. S. H. has by his mar- 

 riage with the normal N. G. one son, 1156.1 cT. 



On external examination and in photographs the hands of 1156.1 cf 

 C. R. H. (b. May 23, 1907) look normal. The distance between the 

 second and third grooves at the inside of the indices looks perhaps 

 slightly shortened and the second phalanges of the indices seem to be 

 a httle narrower than usual in a normal hand. It can not be denied 

 that the shape of the index fingers as a whole reminds one somewhat 

 of the B-type brachyphalangy. 



The radiographs, however, give measures of the phalanges which 

 fall well inside the limits of variation in normal hands. The lengths 

 of II 2 and IV 2 are 17 and 21 mm. on the right hand, 17 and 22 mm. 

 on the left hand. 



The second phalanges of the indices are a little irregular, showing 

 slightly obUque terminal articular surfaces; but the irregularities men- 

 tioned are so slight that the examination as a whole leads to the result 

 that 1156.1 cf is a normal individual, free from brachyphalangy. With 

 the above-mentioned special features in mind it is perhaps safe, how- 

 ever, to make a reservation until this conclusion can be confirmed by 

 examination of the descendants of the individual. 



The investigation of 1151.2 9 explains why this reservation seems 

 indicated. 



