22 THE EVOLUTION OF LIVING BEINGS. 



viduals of different constitutions and from this, experi- 

 mentally established, fact Jordan drew the well foun- 

 ded conclusion: 



The Linnean species is no species. 



Yet, up to the present moment, one has continued 

 to speak of it as such, and this has caused endless 

 trouble. Most decidedly the time has come to break 

 with this wrong designation. 



I nowpropose to do soand to replace thename Linnean 

 species by the neutral name : LINNEON and to define : 



A Linneon as the total of individuals which resemble 

 one another more than they do any other individuals. 



The different types, faithfully reproducing their 

 kind which can be distinguished within the Linneon, 

 Jordan now called, quite reasonably: species. They 

 have subsequently been called: mikrospecies, Jorda- 

 nian species, subspecies, small species or elementary 

 species indiscriminately. 



The question remains: are they really species e. g. 

 have all individuals belonging to a Jordanian species 

 identical constitutions ? 



The answer depends on what answer must be given 

 to the question : 



Is the standing of the test offaithfull reproduction by 

 seed, proof of specific purity? The answer unfortunately 

 is an emphatic: no. 



We know that there are f . i. two kinds of white mice, 

 externally indistinctible, reproducing their kind faith- 

 fully and yet of different constitutions, as becomes at 

 once apparent upon mating a female of each kind with the 

 same black male. The youngs of the one female will then 



