Dixon and Atkins — Osmotic Pressures in Plants. 



451 



see, the opposite is the case. The explanation of the uniformity is obviously 

 the fact that the leaves examined iu each case are on the whole about the 

 same age — owing- to the more or less continuous growth of the ever- 

 green, and consequently possess approximately tlie same coucentration of 

 electrolytes. 



NOV. DEC. JAN. FEB. MAR. APRIL MAY JUNE JULY AUG. SEPT. OCT. NOV. 



Ilex aquifOlium. — Mature Leaves. 

 Fig. 2. 



The uppermost curve — that tracing the clianges of the total concentration 

 of solutes and total osmotic pressure — is also quite different from that of 

 Syringa. In fact, while the osmotic pressure of Syringa is at a maximum in 



