180 Intracellular Transmission of Characters 



character of the species. These qualities can either be 

 seen directly under the microscope, or they betray their 

 presence by definite functions. That the hereditary char- 

 acters lie in the respective organs of the protoplasts can 

 hardly be doubted. But whether they also lie thus in cells 

 where they are present only in the latent condition is not 

 disclosed by the processes of vegetative propagation. 



Here the process of fertilization serves as a clue. Hy- 

 brids teach, and daily observations on man confirm the 

 fact that children, on an average, receive their character- 

 istics, to the same extent, from both parents. But the 

 fertilized egg-cell receives its organs from the mother 

 only, while from the father only the sperm-nucleus 

 conjugates with the nucleus of the egg-cell. All the 

 hereditary characters of the father must therefore 

 be transmitted in the nucleus, as potentialities in a 

 latent state. And before they can become active in the 

 other organs of the protoplast, they must evidently be 

 transported to the latter ones from the nucleus. This 

 transmission is therefore a hypothesis, the assumption of 

 which may well be regarded as a necessity at the present 

 state of our knowledge. 



May I be allowed to illustrate this transmission by a 

 few examples. I take them from hybrids, because here 

 the relations lie most clearly and convincingly before us, 

 and I chose the colors of the flowers bec?use they are 

 easily observed. 



Let us first take the red color of flowers. Phase o- 

 lus multiflorous has red flowers, Phaseolus vulgaris nanus 

 white ones. By pollinating the latter with the pollen of 

 the former there came about several times, in 1886, in my 

 own cultures, -a hybrid seed. This does not deviate ex- 

 ternally from the normal seed of its mother-plant, but it 



