202 HALFDAN BRYN 



that of the parents and to approach to the average index of the type. 

 But in the case of parents having an index considerably higher (e. g. 

 no. 60) the index of the offspring is, however, considerably lower. 

 Only in no. 11 parents and offspring have about the same index. In 

 no. 11, however, 2 of the children were young; one 4 years old, the 

 other 6 years old necessitating some reduction with regard to the off- 

 spring. In all cases the index of the offspring tends to index 83, 

 whether that of the parents is a little above or a little below this value. 

 This favours the supposition that these individuals belong to a biotype 

 with an index about 83. In table 3 the cases are placed where one 

 of the parents has a high index, the other a medium index. As seen, the 

 average proportion is 83,5 and 76,2. Phenotypically one of the parents 

 is brachycephalic the other mesocephalic, or in two cases even dolicho- 

 cephalic. Still all offspring of this group is, as seen, phenotypically 

 brachycephalic; in some cases the offspring has even a much higher 

 index than any of the parents. The average index of all parents of 

 this group is 79,8; whereas the average index of the offspring is 83,25. 

 One of the parents has in other words stamped all the offspring. In all 

 these families the children have a higher average index than their 

 parents. In other words, the higher index is dominant to the medium 

 index. It is apparent from table 4 that no change takes place in this 

 respect even if the index in the other parent should be still lower. 

 In this group one of the parents is brachycephalic, the other dolicho- 

 cephalic; their offspring, however, is largely brachycephalic. The 

 average index in the two parents is respectively 84,3 and 74,6. The 

 average index in all the offspring is 84,2. From this we must conclude 

 that the brachycephalic type is dominant also when interbred with in- 

 dividuals phenotypically dolichocephalic. 



In table 5 we meet with an entirely new phenomenon, viz. the 

 heterogeneity of the offspring. In no. 14 both parents are apparently 

 largely brachycephalic. All the children have a lower index, and it will 

 perhaps in years to follow decrease still more. In no. 32 both parents 

 have about the same index, 81 à 82. Of the offspring some have a 

 considerably lower index, some a considerably higher one. The same 

 is even more prominent in no. 4, where 5 of the children have an 

 index considerably higher than either of the parents. It is evident 

 that we here face more complicated problems than those already dis- 



