Recombinations of the Primary Hereditary Characters 187 



we have by division, reduction, and reunion obtained a 

 totally different combination. 



In other cases, nuclei with the same original combination 

 will give still different results ; there are 81 diverse resultant 

 combinations that may be produced in this way from a sin- 

 gle nucleus having the combination of packets supposed 

 above. 



Since the facts as to the recombination and distribution of 

 these primary hereditary characters are the same in Pro- 

 tozoa and in higher organisms, we may expect them to pro- 

 duce the same results. That is, we may expect to find Men- 

 delian inheritance in Protozoa, when the facts are fully stud- 

 ied. Mendelian inheritance is nothing more nor less than a 

 recombination and distribution of the secondary hereditary 

 characters in the manner that the primary hereditary char- 

 acters are recombined and distributed, without doubt in 

 consequence of this recombination and distribution of the 

 primary characters. 



There is, of course, no reason to expect such a Mendelian 

 distribution of inherited characters among the progeny of a 

 single individual that divides after conjugation. All such 

 progeny will probably be alike, save for any accidental vari- 

 ations in the splitting of the chromosomal packets ; this, as 

 we have seen, observation shows to be the case. But if the 

 progeny are examined from a large number of pairs coming 

 from two diverse races that have been induced to conjugate, 

 we may expect to find among these the typical Mendelian 

 distribution of characters. 



This may be illustrated most directly by the inheritance 

 of the primary characters (the chromosomes) ; we know that 

 the secondary hereditary characters follow the primary ones. 



Let us suppose, for example, that in the two races a pair 

 of chromosomes differ ; we will say that they are black in one 



