18 THE DATE PALM. 



Differences in the thicknesses of the stems and in the number 

 of functional leaves borne by the plants can, therefore, only be 

 of use as identifying factors where the varieties of date trees to 

 be compared are known ; where their stems normally differ 

 materially in thickness, and where they are growing under similar 

 conditions. Very frequently parts of old flower-clusters remain 

 attached to the tree after the flowering and fruiting seasons are 

 over, and in such cases the sex of the tree can usually be identified 

 with certainty. (For structure of the inflorescences and flowers 

 see pages 11 13, paras. 6 10, and for date that the trees come 

 into flower (see page 92, para. 59). 



