88 



ALTERATION OP POSITION. 



In Tradescantia virgmica I have met with opposite 

 connate leaves ; the altered position, however, being 

 due to the union of two stems. 



Twisting of the stem is a frequent cause of the dis- 

 placement of leaves (see spiral torsion), as also hyper- 



J 



Pio. 40. Large-coloured leaf occupying the position of the inflores- 

 cence in Oesnera, after Morrcn. 



