The Elements of the Species. 



61 



mutation new characters arise all at once. Such char- 

 acters are however just as variable, and vary in the 

 same way as those specific characters with which we are 

 already familiar.^ There are so many examples of this 

 rule that it is difficult to make a choice.- Zea Mays tiuii- 

 cata or cryptosperina has its seeds enveloped in husks, but 

 the length of these husks varies in a high degree ; some- 

 times they scarcely cover the seed, in other ears they are 



Fig. i6. Leaves of Soxifraga crassifolia in various 

 degrees of pitcher formation, the succeeding stages 

 being reoresented by the figures 1-5. This process 

 can be imagined as consisting in the edges of the 

 leaves folding upwards and fusing together. The 

 degree of this fusion is seen to be very variable. 



3 or 4 times as long, if not more. Very often they are 

 much longer in the lower part of one and the same ear, 

 than in the upper; and their length gradually decreases 

 as the apex of the ear is approached (Fig. 15). Varie- 

 gated leaves, double flowers, pitchers (Fig. 16), split 

 leaves and so forth occur in great variety, and it would 

 not be difficult to demonstrate the applicability of Oue- 



^ See also Intracellulare Pangenesis, pp. 69-70. 



^For examples from the animal kingdom see Bateson, Mate- 

 rials, p. 68. 



