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against the danger of too rapid transpiration from the 

 increased leaf surface, at the same time forming- passages 

 through which the water on the surface may be drawn 

 within. The raised stomata enable the plant to throw 

 off sufficient water to render the flow from the roots 

 upward unbroken, this moisture is allowed to escape very 

 slowly and if the outward conditions are such as to 

 condense even a small amount of moisture on the leaf 

 surface, it may still be sufficient to prolong the life of 

 the plant through a period of drouth, if not to enable it 

 to create new building material necessary for growth. 

 Salvia argentea L. originates from Southern Europe, 

 along the coast of the Med. sea, Spain, Sicily, Crete &c. 

 It is much more difficult to learn accurately concerning 

 the influences surrounding this plant, as the territory 

 over wich it is spread is so much greater, and the liabi- 

 lity to variation of climate thus increased. One thing, 

 however, is certain, that is, notwithstanding both soil 

 and climate are here much more favorable to vegetable 

 activity than in the former case described, still in nearly 

 every section where this plant is said to appear, the 

 period of growth is interrupted by a dry season, causing 

 a stillstand in this process of greater or less duration. 

 For example, in Spain vegetation is said to make rapid 

 progress in spring-time, its course is then suddenly 

 checked by the summer's drouth, to begin again when 

 the fall rains occur. In other sections the time varies, 

 the greater amount of rain falling in summer and the 

 longest period of growth occurring then, but in few 

 localities, if indeed in any, of this whole region, is the 

 rainy season of sufficient length to enable a plant like 

 Salvia to begin and finish its growth uninterrupted by a 



