ON NEW PLUMS AND PRUNES 



nal nucleus there are to be seen sundry films of 

 matter, arranged to form a sort of skeleton, which 

 are readily stained under his manipulation and 

 which he therefore names "chromosomes", colored 

 bodies. He observes that the nuclei in the cells of 

 different plants and animals have these infinitesi- 

 mal chromosomes arranged in different character- 

 istic groups, differing in number in different 

 species but always the same for each and every 

 cell of plants or animals of a given species. 



The enlarged vision of the microscopist enables 

 him to assure us that when two germ cells of the 

 opposite order come together when, for example, 

 the nucleus of a pollen grain blends with the 

 nucleus of the plant ovule there are various char- 

 acteristic dividings and interlinkings between the 

 two sets of chromosomes within the two nuclei. 



In the blending and rearrangement of these 

 minute structures, he believes that he is witnessing 

 the underlying processes that bespeak the blending 

 of hereditary potentialities and their re-combina- 

 tion to determine the future possibilities of the 

 new organism that is thus brought into being. 



All this is very wonderful. But it brings us after 

 all only one stage nearer the confines of the mys- 

 tery. The chromosomes within the nucleus, which 

 all biologists nowadays regard as the tangible car- 

 riers of hereditary tendencies or capacities, are 



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