280 RELATION OF PHYLLOTAXIS TO MECHANICAL LAWS. 



The general application of this assumption of anisophylly in 

 the phyllotaxis system is plotted in fig. 97 for the simple decussate 



Fig. 97.— Eccentric growth, system for oneutation and approximate anisophylly 

 of the members of (1 + 1), (2 + 2), and (3 + 3) systems. 



the posterior. At a slightly older stage, when the flower stalk is 2 mm. long, 

 the construction appears equalised, and the receptacle takes on a uniformly 

 orateriform outline. By the time, however, that the ovules arise in the ovary 

 and the bud attains a length of 1-5 mm., the eccentricity is definitely reversed 

 and the posterior side is distinctly larger than the anterior, and this again 

 becomes increasingly exaggerated in the older bud and flower. 



