1 66 Heredity and Eugenics 



through selection, but how selection is conceived to pro- 

 duce these results depends very largely upon an endless 

 array of unproven neo-Darwinian assumptions. 



Hybridization is known to be productive of germinal 

 variations, and in domesticated organisms a considerable 

 number of useful forms have thus arisen. Frequently, 

 howexer, these commercial hybrids, appearing to be con- 

 stant, are only first generation hybrids indefinitely per- 

 petuated by cuttings, as are many kinds of oranges, apples, 

 grapes, etc., and most of these, if allowed to reproduce 

 sexually, would in subsequent generations break up into 

 the component tj'pes out of which they were built. There 

 is evidence, howe\'er, to warrant the assumption that 

 hybridization does result in the development of permanent 

 modifications which are new to the strain in which they arise, 

 and which persist indefinitely. Moreover, hybridization is 

 a potent means of creating new and diverse combinations 

 of existing qualities and attributes, which may account 

 for no smaU portion of the "species" in nature, as well as in 

 domestication. To what extent hybridization is a source of 

 germinal variations in nature is undetermined, and this 

 condition is largely due to the persistence of the dog- 

 matism that hybridization is of rare occurrence, is ab- 

 horrent to species in nature, and is really a product of 

 domestication and the supposed loss of specific integrity 

 and chastity induced by man and cultivation. Statements 

 of this kind, however, are entirely a-priori orthodox preju- 

 dices without foundation in fact. Recent work, especially 

 by botanists, shows a considerable and increasing array of 

 hybridizations occurring in nature, for example, in violets, 

 which exhibit an abundance of crossings, with manj- resulting 

 hybrids. Moreover, this condition is by no means limited to 



