202 A Defence of Mendel's 



we know so well elsewhere. Such a fact would in nowise 

 diminish the importance of Mendel's discovery. The fact 

 that mosaic peach-nectarines occur is no refutation of the 

 fact that the total variation is common. Just as there 

 may be trees with several such mosaic fruits, so there may 

 be units, whether varieties, individual plants, flowers or 

 gonads, or other structural units, bearing mosaic egg-cells 

 or pollen grains. Nothing is more likely or more in 

 accordance with analogy than that by selecting an in- 

 dividual producing germs of blended or mosaic character, 

 a race could be established continuing to produce such 

 germs. Persistence of such blends or mosaics in asexual 

 reproduction is well-known to horticulturists ; for example 

 "bizarre" carnations, oranges streaked with " blood "- 

 orange character, and many more. In the famous paper of 

 Naudin, who came nearer to the discovery of the Mendelian 

 principle than any other observer, a paper quoted by 

 Professor Weldon, other examples are given. These forms, 

 once obtained, can be multiplied by division ; and there is 

 no reason why a zygote formed by the union of mosaic or 

 blended germs, once arisen, should not in the cell-divisions 

 by which its gametes are formed, continue to divide in a 

 similar manner and produce germs like those which united 

 to form that zygote. The irregularity, once begun, may 

 continue for an indefinite number of divisions. 



I am quite willing to suppose, with Professor Weldon 

 (p. 248), that the pea Stratagem may, as he suggests, be 

 such a case. I am even willing to accept provisionally as 

 probable that when two gametes, themselves of mosaic or 

 blended character, meet together in fertilisation, they are 

 more likely to produce gametes of mosaic or blended 

 character than of simply discontinuous character. Among 

 Messrs Button's Primulas there are at least two striking 



