50 Plants and their Ways in South Africa 



light. The distance from the midrib of one leaf to that of 

 another is one-third the distance around the stem. What leaf 

 will come over the fourth ? This may be found by drawing a 



Fig. 57.— Spirals showing J, §, § Phyllotaxy. 



spiral and dividing it into three sections. Imagine the centre 

 to be the tip of the stem. Beginning where one of the lines 

 cuts the outer end of the spiral, place leaf number one. Two 

 and three will fall on the other lines. The fourth will be in 

 line with the first. By placing each succeeding leaf one-third 



