16Section I.G. Sergi. 
17* Boas ... ... Changes in bodily form of Descendents of Immigrants. Washington, 
1910. 
)> ••• ... Abstract of the Report of Changes, &c. Washington, 1911. 
18. Radosavljevich, P.R. Prof....Boas’ New Theory of the Form of the Head. A critical 
contribution to School anthropology. Amer. Anthropologist, 
XIII., 1911. 
19. Brainerd, E. ... The behaviour of the seedlings of certain violet hybrids. Science, 
N.S., XXV., 1907, Pag. 940 
20. Keith, A.... ... Certain Phases in the Evolution of Man. British Medical Journal, 
March 30, April 6, 1912. 
21. Treasury of Human Inheritance. University of London. Francis Galton, Laboratory 
for National Eugenics. London 1907-1912. Eug. Labor. 
Memoirs I.-XV. 
VARIATION AND HEREDITY IN MAN. 
By Professor G. Sergi, 
Professor of Anthropology, University of Rome. 
These are two problems connected with each other to the solution of 
which scientists have directed their greatest efforts, but up to the present 
owing to the great complexity of the characters which living organisms 
possess, a complete solution has not been reached. Moreover, the methods 
employed in seeking the facts and in interpreting them are various, and, 
indeed, often opposed to one another. 
Variability and variations, inheritance and heredity of characters are 
ideas and expressions intimately associated with each other. The 
phenomena of heredity and variation, considered apart from the difficulties 
raised by the inheritance of certain characters and the multiform variability 
of such characters, would no doubt lend themselves to an explanation more 
easily discoverable, and would suggest a simpler method for their ascertain­ 
ment and a simpler theory of their origin. If, then, we stopped at the 
surface of the facts, as they appear directly to the observer, and did not 
enquire into the inner processes, we should easily be able to account for 
them, as some believe they can already do. 
In the study of variations one difficulty which cannot be 
avoided is the question of their determining causes: Is it that 
external forces influence living beings to make them vary, or is 
it that internal conditions of the same living organism determine its 
variability? Each idea has its separate supporters. Nor is this all. The 
variations which living organisms undergo—are they of one kind only or 
of various kinds? And are they transmitted equally whatever be their 
nature, or are only some of them transmitted? The scientist knows from 
the time of Lamarck to Darwin, and from Galton to Weissman, what has