NORMAL FIBONACCI PHYLLOTAXIS. 



85 



inherent growth movements tend to become circular in section, as 

 for example they would if they were merely semi-fluid masses 

 contained in a uniformly elastic membrane. 



A circle inscribed within the orthogonal area with a definite centre 

 of its own, which is not the true centre of construction, may he thus 



Fig. 28. — Log. spiral construction (3 + 5) 



taken as representing the actual primordium within the error of 

 drawing or observation.* 



Since also the true curve is an ovoid, and the ratio of distances 

 between the new growth centres must be measured along the 



* That is to say, since comparison can only be made between similar figures. 

 Cf. Mathematical Notes. 



