122 PHARMACEUTICAL BACTERIOLOGY 



(chromosomes) were considered to be the carriers of and the transmitters of 

 the hereditary characters, of the cell and we have come to believe that there 

 can be no new cell except from a mother nucleus, at least as far as pertains 

 to cells which have nuclei. While it is generally believed that the germatic 

 and the somatic cells have distinctive inherent properties which are not 

 capable of being transmitted from the one kind of cell to the other, there are 

 those who maintain that the nucleus, if not the cell plasm, has a dual 

 nature, that it possesses both somatic and germatic properties, and that 

 the somatic cells and the germatic cells are therefore potentially inter- 

 changeable. In fact some investigators have suggested the possibility of 

 the functional interchangeability of somatic and germatic cells and also 

 of the male and female germ cells, a contention which has been proven to 

 be correct at least as far as it applies to the lower forms of plant and animal 

 life. Of great interest have been the recent experiments in ovarian and 

 testicular transplantation made by Castle, Stanley and others, the results 

 of which tend to prove the correctness of the Weissmannian theory of the 

 transmission of hereditary qualities. For example, the Guinea pig off- 

 spring derived from a transplanted ovary possessed the qualities of the 

 mother from which the ovary was taken and not those of the pig into which 

 the ovary had been transplanted. 1 We must not forget the epochmaking 

 experiments of the Austrian monk Mendel (18221884) and the Mendelian 

 law of the transmission of hereditary qualities. Mendel demonstrated 

 that the gametic fusion of different ancestral characteristics did not give 

 rise to a blend of such characteristics, but rather that there was a continua- 

 tion of the hereditary qualities of both gametes in dominant and recessive 

 proportions. It is surprising that this fundamental principle or rule in 

 gametic or sexual reproduction was not noted earlier. It must have been 

 apparent to all observers that the combining of male and female hereditary 

 sex characteristics, as must be the case in every gametic fusion, did not as 

 a rule result in a hermaphrodite or sexually neuter being. The child does 

 not inherit a blend of paternal and maternal characters. A son may in- 

 herit the physical characters from the maternal side of the house and the 

 mental and moral characters from the paternal side. The offspring of an 

 ill tempered and an indifferent parent does not grow into an even or 

 happily tempered person. Both characteristics may be present, one 

 dominant and the other recessive but not as a blend. In this connection 

 might be mentioned the theory of male dominance as promulgated by 

 Galton and others. That is, the offspring manifests to a dominant 

 degree the paternal hereditary qualities. There are however numerous 

 exceptions to this rule. 



1 Experimental tissue transplantations, tumor transplantations and grafting, show 

 similar results. 



