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which it is connected by numerous pores, these cells are 

 also connected together in the same way and are thinner 

 walled than the lower end of the stem cell. From the 

 other end of the stem spread the long branches in every 

 direction, these seem entirely solid, probably not cut off 

 from the stem cell by a wall, the outer surface is scaly 

 and the hairs stand so close together that a dense filz 

 is formed by the interlacing branches. A salt solution 

 was applied, this time of unknown strength, and the stem 

 cell responded at once to the action of the salt by be- 

 coming plasmolytic. 



So throughout the whole list, no example is given 

 in which the hair did not have one or more living cells 

 in immediate connection with the epidermis. 



We have thus shown that the leaves of the plants 

 placed in the first and second classes are furnished with 

 a special apparatus, one of whose functions may be, to 

 aid in supplying the plant with water from the atmo- 

 sphere. 



In the third class this arrangement is wanting. Here 

 the hair cells are either entirely unseptirt, consisting of 

 a single epidermal cell which has prolonged itself into 

 a long hair, or an epidermal cell divides at first into 

 several, which then grow into shorter horn-like projec- 

 tions, spreading in all directions over the surface of the 

 leaf. In both cases the walls are either thickened so as 

 to contain only a small lumen, or they remain thin, the 

 cells losing their contents at an early stage, so that those 

 of the mature leaf contain air, or are quite empty, the 

 walls pressed together. 



From this difference in anatomical structure, it would 

 follow that if the reasoning in reference to the two former 



