SIZE CHARACTERS SEEMING TO :< BLEND." 21 



The stature of man has been studied by Bean (1910) among Fili- 

 pinos. He makes the following statements (p. 44) : 



"The study of the students by the method of grouping reveals types that 

 apparently represent character-complexes composed of unit characters that obey 

 Mendel's laws in heredity. A character-complex is a group of characters, such 

 as the small stature, broad head, and broad nose of the Primitive, that hangs 

 together in heredity or breaks up when crossed with another character-complex, 

 such as the tall stature, long head, and long nose of the Northern, in the forma- 

 tion of new character-complexes which are recombinations in all possible ways of 

 the individual characters, the original character-complexes being also retained." 



Davenport (1911, pp. 42, 43) draws up the following laws of the 

 inheritance of human stature, which suggest Mendelian phenomena at 

 the bottom: 



"The first general law is that, in case the four grandparents are very unlike, 

 the adult children will vary greatly in structure, whereas when the grand- 

 parental statures are closely alike those of the children will be also. * * * 

 The second general law is that when both parents are tall all of the children 

 tend to be tall; but, on the contrary, if both parents are short some of the 

 children will be short and some tall in ratios varying from 1 : 1 up to 2 : 1. 

 If all of the grandparents are short then there tend to be twice as many short 

 children as tall; but if one grandparent on each side be tall there will tend to 

 be an equality of short and tall offspring." 



SIZE CHARACTERS SEEMING TO "BLEND." 



Although blending inheritance, in which offspring are always geneti- 

 cally intermediate between their parents regardless of the characters of 

 their grandparents, has been generally believed to describe the phe- 

 nomena observed in the inheritance of size characters, this is based on 

 a small number of cases, none of which has been critically investigated. 

 Very influential evidence in favor of the theory of blending inheritance 

 has been the epoch-marking work of Sir Francis Galton (1889 and 

 1897) on human stature and Basset hounds. By studying pedigrees 

 with statistical methods he arrived at his Law of Ancestral Inheritance, 

 which Tschermak (1905) characterizes as follows: 



"Die Grundidee der Galtonschen Lehre vom Ahnenerbe mochte ich dahin 

 charakterisiren, dass die Eigenschaften der einzelnen Ahnen eines Individ- 

 uums fiir dessen Aussehen in gesetzmassiger weise bestimmend sind. Es 

 wird demnach wenn ich so sagen darf eine rein genealogische wertigkeit 

 der einzelnen merkmale, je nachdem sie den vater oder der mutter, den Grossel- 

 tern oder noch ferneren ahnen zukamen, behauptet und zwar in einer gesetz- 

 massig fallenden Progression." (Arch. f. Rassen u. Gesellschafts Biol., vol 

 2, 1905, p. 663.) 



In the work with the pedigrees of the Basset hounds there is found 

 a most surprising agreement between the facts and the results expected 

 on the basis of this theory. The work of the school of statisticians 

 founded by Galton and led by Pearson has been voluminous. It has 

 undoubtedly revealed important facts about populations, racial tenden- 



