136 



THE LIVING CYCADS 



The lower leaflets of the seedling differ from those of 

 the adult in many species. In Dioon spinulosum the 

 lowest pair of leaflets is nearly as large as any of the rest 



Fig. 77. — Dioon spinidosum: young plant with new leaves, showing 

 reduced leaflets at the base and leaves of the previous crown with no 

 reduced leaflets. 



until the plant reaches the age of eight or nine years, and 

 during this period the part of the midrib below the 

 lowest pair of leaflets is about as long as the part bearing 



