Phenomena of Inheritance 65 



more distant ancestor more than either jparent. Sometimes 

 actually new characters arise in descendants which were not 

 present in ascendants, but which are thereafter inherited. Ac- 

 cordingly inherited characters may be classified as resemblances 

 and differences, though both are determined by germinal organi- 

 zation, or heredity. There is therefore no fundamental difference 

 between inherited similarities and dissimilarities. Heredity and 

 variation are not opposing nor contrasting tendencies which make 

 offspring like their parents in one case and unlike them in an- 

 other; really inherited characters may be like or unlike those of 

 the parents. 



On the other hand many resemblances and differences between 

 parents and offspring are due not to heredity at all, but to environ- 

 mental conditions. By means of experiment it is possible to dis- 

 tinguish between hereditary and environmental resemblances and 

 differences, but among men where experiments are generally out 

 of the question it is often difficult or impossible to make this dis- 

 tinction. 



t 

 I. HEREDITARY RESEMBLANCES 



1. Racial Characters. All peculiarities which are characteris- 

 tic of a race, species, genus, order, class and phylum are of course 

 inherited, otherwise there would be no constant characteristics of 

 these groups and no possibility of classifying organisms. The 

 chief characters of every living thing are unalterably fixed by 

 heredity. Men do not gather grapes of thorns nor figs of thistles. 

 Every living thing produces offspring after its own kind. Men, 

 horses, cattle; birds, reptiles, fishes; insects, mollusks, worms; 

 polyps, sponges, micro-organisms, all of the million known spe- 

 cies of animals and plants differ from one another because of 

 inherited peculiarities, because they have come from different 

 kinds of germ cells or protoplasm. 



2. Individ-mil Characters. Many characters which are pecu- 

 liar to certain individuals are known to be inherited, and in gen- 



