THE CELL THEORY 255 
number—commonly from two to twenty-four—in different 
parts of animals and plants, they are, nevertheless, of the 
same number in all the cells of any particular plant or ani- 
Fic. 78.—Highly Magnified Tissue Cells from the Skin of a 
Salamander in an Active State of Growth. Dividing cells with 
chromosomes are shown at a, b, and c¢,. (After Wilson.) 
mal. Asaconclusion to this kind of observation, it needs 
to be said that the chromosomes are regarded as the actual 
bearers of hereditary qualities. The chromosomes do not 
