162 RELATION OF PHYLLOTAXIS TO MECHANICAL LAWS. 



of Archimedean spirals will be subjectively produced, and the 

 orthostichy Hnes thus appear as if they ought to be straight. But 

 until such radial equality is produced the curves cannot be spirals 

 of Archimedes, and the " orthostichies " cannot be straight, what- 

 ever else the nature of the spiral may be. The assumption that 

 the orthostichies should be primarily straight thus entirely falls 

 to the ground, and torsion theories based on such hypotheses are 

 unnecessary. 



