39 



dry season. Again is seen the same necessity as before 

 for a plant provided with no special means for hoarding 

 a water supply, like that of woody or succulent plants, 

 to adapt itself by some other means to the surrounding 

 circumstances. One thing noticed in this connection, may 

 be mentioned here though it may have but little weight. 

 During the time spent in studying these leaves, I 

 noticed carefully from time to time, the difference in the 

 amount of dew found on leaves near the surface of the 

 earth and those a few feet distant. This was often very 

 considerable, leaves a few inches from the ground would 

 sometimes be completely wet with dew, while those one 

 and a half or two feet distant were quite dry. This was 

 especially the case when the dew was light, in case of 

 a so-called heavy dew the difference was less perceptible. 

 The lower leaves of Salvia argentea are crowded on the 

 stem, covered on both sides with a most complete and 

 beautiful filz, while those higher up on the stem are more 

 scantily furnished with hairs, many of the extreme upper 

 ones being not really filzig. 



Phlomis fruticosa and Lavatera oblongifolia originate 

 from the same localities as Salvia argentea, therefore 

 must have been subjected to similar influences. Alfredia 

 cernua has its home in Siberia, grows on stony places. 



This reasoning in regard to the raised stomata and 

 their connection with an inclosed air space about the 

 epidermal surface can also be applied to the plants 

 forming the third class, though the hairs here appear 

 to play a less important part, and the objection before 

 suggested, that a thinner coating of filz and level stomata 

 would serve just as well for protection, may be made 

 here with more force than in case of the two other 



