42 OF .THE MEDULLA OR PITH. 



that the moisture of the medulla varies, let 

 the leaves be ever so flaccid. I cannot but 

 incline therefore to the opinion that the 

 medulla is rather a reservoir of vital energy, 

 even in these bulbous grasses. 



Mr. Knight has shewn that the part in 

 question may be removed without any great 

 injury to a branch, or at least without im- 

 mediate injury, but I have had no oppor- 

 tunity of making any experiments on this 

 particular subject. 



