Proceedings of the Ohio State Academy of Science 349 



cannot hold for the heterosporous pteridophytes, for the zygote 

 produces a bisporangiate plant and the sex of the gametophyte 

 is determined independently of the reduction division not in a 

 Mendelian ratio but in some species in the proportion of 5,000 

 males to one female. 



According to Wilson, the eggs are all alike, while the sperm- 

 atozoa are of two sorts half bearing the same character as the 

 ■«ggs and half being without it. But Bateson and his associates 

 find that in the moth Abraxas grossulariata and in a canary bird 

 studied by them, the eggs are dimorphic in sex tendency whereas 

 the spermatozoa are all alike. 



The apparently antagonistic results brought to light are 

 really only antagonistic when viewed from the standpoint of the 

 several contradictory hypotheses of sex-determination. If we 

 take a reasonable view of sexual inheritance, regarding it as a 

 connnon inheritance of the race which may express itself in one 

 way or the other, as ordinary vegetative characters, the pecu- 

 liarities presented will be readil}- explained on the same basis as 

 the various vegetative polymorphisms to be found in the higher 

 plants, the play of hereditary factors and the result of heredi- 

 tary expression being much greater than what is shown by Men- 

 delian inheritance. 



GENERAL CONCLUSIONS. 



The principles maintained in the foregoing discussion are 

 either based on or lead to the following general conclusions and 

 hypotheses : 



1. Every cell of an organism contains all the general 

 Tiereditary characters or units of the entire individual body. 



2. Only a part of these characters come to expression at 

 any given stage of development. 



3. Some hereditary characters are common to all the or- 

 gans or parts of the hereditary apparatus, others to individual 

 chromosomes. 



4. Peculiarities of form and function come to expression 

 by the coml)ined activity of groups of cells as well as by the 



