GENERAL OBSERVATIONS. 29 



obtaining in a transverse plane at the growing apex of a stem, 

 and the whole forms a striking image of a growing point covered 

 with primordia which tend to assume the form of spheres. 



It will be further noted that the structure cannot be defined 

 in terms of the Schimper-Braun theory. As in the case of the 

 Pine cone, no formula can be given for it except that which 

 includes the number of intersecting parastichies. But on the other 

 hand, the older theory gave a method for constructing the diagram, 

 which, even if erroneous, was almost within the limit of the error 

 of observation. Clearly no advantage is to be gained by throwing 

 away the Schimper-Braun construction until it can be replaced by 

 a better. If the number of curved parastichies gives the only 

 strictly accurate account of the system, it becomes necessary to 

 examine these curves and see if they can be brought into line with 

 mathematical terminology and geometrical methods of construction. 



