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influences to which the plant is exposed. So exact is this 

 fitness, that it is claimed that the climate of the country 

 in which a plant originates, may be determined from a 

 knowledge of the mechanism of its stomata. We must 

 exclude from the number, however, all those plants which 

 have been subjected to the influences of continued culti- 

 vation as here too many unknown conditions may have 

 been introduced to render possible an accurate judgment. 

 The form of stoma which we have referred to as ^raised 11 

 is that where the schliess-cells are lifted a little from 

 the epidermal surface. This may be effected by a number 

 of the cells joining these, or by a single epidermal cell 

 in which the stoma lies projecting from the surface. 

 The latter is a peculiarity of Aneimia fraxinifolia. 



Disregarding the more minute details of the structure 

 of these organs, this raised form is universally admitted 

 to be the form best adapted for transpiration. It is found 

 accordingly, on a number of species of ferns growing in 

 the East Indies (Indian Monsoon Region) where the 

 moisture of the air currents coming from the sea and 

 condensing against the mountain sides, keeps the air 

 perpetually moist, and the soil also contains an abundant 

 supply of water. These leaves are destitute of any hair 

 covering, their stomata are thus in immediate connection 

 with the moist warm atmosphere. Their form together 

 with their surrounding conditions furnishes an exact con- 

 trast to the sunken stomata found on plants inhabiting 

 countries where the air contains but little moisture. The 

 natural inference therefore is, that the raised stomata 

 are in this case, especially fitted to aid transpiration 

 which would otherwise be too much impeded by the 

 nearly saturated condition of the atmosphere. 



