THE CELLULAR BASIS 177 



were vertebrates and produced eggs of the 

 vertebrate pattern; but the color of our skin 

 and hair and eyes, our sex, stature, and mental 

 peculiarities were determined by the sperm as 

 well as by the egg from which we came. There 

 is evidence that the chromosomes of the egg 

 and sperm are the seat of the differential fac- 

 t^'S or determiners for Mendelian characters, 

 while the general polarity, symmetry and pat- 

 tern of the embryo are determined by the cyto- 

 plasm of the egg (see p. 263). 



It will be observed that the correlation be- 

 tween chromosomes and adult characters is 

 different in kind from that between the cyto- 

 plasm of the egg and the adult characters; in 

 the latter case polarity, symmetry and pat- 

 tern are of the same kind in the egg and in the 

 adult, and the correspondence is comparatively 

 close; in the latter there is no correspondence 

 in kind between the chromosomal peculiarities 

 and the pecularities of the adult. This fact 

 might suggest that the chromosomal organiza- 

 tion may be more fundamental than that of 

 the cytoplasm. There are reasons for believ- 

 ing that many substances of the cell are formed 



