12 



EFFECT OF SOLUBLE SALTS UPON PLANTS. 



EFFECT ON THE SIZE OF THE EPIDERMAL CELLS. 



Table II gives the results of measurements, expressed in microns, 

 of the average length and height of the epidermal cells of the upper 

 leaf surface of three species of plants grown in soils containing differ- 

 ent concentrations of soluble salts and of control plants grown in 

 nonsaline soils. 



Table II. — Dimensions cf epidermal cells of the upper leaf surface of different plant 

 species grown in soils containing various concentrations of soluble salts/ 1 



Plant. 



Soil containing 1 Soil containing i Soil containing 2 



r m tmi r. lft n per cent total 1.5 per cent total per cent total 



qqHtio \w3n i salts (estimated salts (estimated salts (estimated 

 banne s»oii i . Q j per cent j per cent L4 per cent 



sodium chlorid) . sodium chlorid) . sodium chlorid) . 





Length. 



Height. Length. 



Height. 



Length. 



Height. 



Length. 



Height. 



Wheat ( Triticum durum) ... 



50.5 

 41.9 

 44.6 



V- 



50.9 



33.2 



37.2 



29.8 

 34,3 

 37.5 



26.0 

 30.6 

 34.3 



40.3 

 31.4 



30.8 



34.1 

 29.5 

 36.3 



29.4 



36.8 







26.0 



27.5 



Barley {Hordeum distiehum i 

 Average 













45. 7 40. 4 33. 9 



1 



30.3 i 34.2 



33.3 | 33.0 



1 



26.8 



a Tae figures represent in each case averages of about 100 measurements. 



Table III gives the results of measurements expressed in microns 

 of the average length and height of epidermal cells of the lower leaf 

 surface of three species of plants grown in soils containing different 

 concentrations of soluble salts and of control plants grown in non- 

 saline soil. 



Table III. — Dimensions of epidermal cells of the lower leaf surface of different plant 

 species grown in soils containing various concentrations of soluble salts. " 



Plant. 



Control (non- 

 saline soil) . 



Soil containing 1 



per cent total 

 salts (estimated 



0.7 per cent 

 sodium chlorid). 



Soil containing 

 1.5 per cent total 

 salts (estimated 



1 per cent 

 sodium chlorid*. 



Soil containing 2 



per cent total 

 salts (estimated 



1.4 per cent 

 sodium chlorid). 





Length. 



Height. 



Length. 



Height. 



Length. 



Height. 



Length. Height. 



Wheat ( Triticum durum) . . . 



47.4 

 45.0 



48.4 

 37.2 



31.9 

 32.3 

 36.2 



v- 



33.2 



33.3 



34.9 

 30.4 



32.3 

 30.6 



30. 8 1 • 24. 1 



27. 9 1 25. 4 



Barley ( Hordeum distiehum i 



44.2 1 44.9 



37. 1 36. 5 



42.2 





Average. 



a The figures represent in each case averages of about 100 measurements. 



It will be seen from Tables II and III that the leaves of the three 

 plants grown in soils containing an excess of soluble salts have on an 

 average smaller epidermal cells than those of the controls, the upper 

 and lower leaf surfaces showing but little difference in this respect. 

 Taking the average for all three species the length of the epidermal 

 cells of the controls on both the upper and the lower surfaces of the 

 leaf averages about 35 per cent greater than that of the epidermal 



134 



