HEREDITARY TYPE OF CHARACTER STUDIED. 55 



When the distribution of these measurements is studied in the cor- 

 relation table it will be seen that they fall into two different groups. 

 One of these forms a group near and parallel to the ''swarm" of normal 

 measures and even overlapping it to some degree, as just mentioned. 

 The individuals whose phalanx measurements belong to this group are 

 all described as brachyphalangous of the B-type. The other group 

 of values forms a ''swarm" of its own in the upper right corner of 

 the correlation table, removed from the other two swarms. The individ- 

 uals from whom these phalanx measurements are obtained show the 

 B !-type of brachyphalangy. 



It will be seen that two values in the classes 8 mm. to 23 mm. and 

 10 mm. to 23 nam. seem to form a connective link between the two groups. 

 But this is merely apparently so. In fact these two measurements 

 are obtained from the individual 1154.1 9 I. S. H. who was 12 years 

 old when the radiographs were taken. The radiographs demonstrate 

 that the epiphysial cartilages of her second index phalanges were 

 already entirely ossified, while those of the second ring finger phalanges 

 are quite normal. This means that the growth in length of the short- 

 ened index phalanges has stopped, while that of the second ring-finger 

 phalanges will keep on for several years. The final result will be that 

 the values, temporarily found in the classes mentioned, when the 

 individual is adult will be found within the "swarm" in the upper 

 right corner. It has been shown that a similar bony condition of the 

 epiphysial cartilages is not found in the radiographs from hands of 

 B-type brachyphalangous children. When this fact is taken into 

 account the two separate groups stand clearly out without any con- 

 necting intermediate link. 



The value found in the 11 mm. to 25 mm. class is obtained from the 

 individual 1942.1 9 . The value representing the measurements from 

 her other hand is found in the 8 mm. to 25 mm. class. The latter 

 value as well as the whole aspect of her indices makes it clear that she 

 belongs to the type whose measurements are grouped in the upper right 

 corner of the correlation table. 



It may be objected to this distinction between the two types that 

 the material is too small. The difference might be due merely to an 

 extreme case of somatic variation of the inherited character and the 

 apparent occurrence of two types might be explained by the fact that 

 we have not happened to meet the individuals showing an intermediate 

 condition. Our material, however, is larger than the radiographs 

 alone indicate. If we take the photographs and the cases where we 

 have reliable information of B !-type brachyphalangy into account — 

 "index fingers with only one joint" — ^we get 16 brachyphalangous 

 individuals of the B-type, 11 of the B !-type. It seems highly improb- 

 able that within this number of individuals representing 14 different 

 families we should not have met a single intermediate case, if we are 

 here dealing with an ordinary somatic fluctuation. If this were the case 



