12 



LOUISE DOSDALL 



TABLE 1 

 Comparison of planimeter and weighing methods of determining leaf areas 



considered so small that the two methods might be used inter- 

 changeably. Whichever method was the more convenient under 

 the circumstances was used to detennine the areas. 



(4) PHOTOSYNTHESIS METHODS 



To determine the efficiency of Equisetum as compared with 

 that of other plants with respect to the activity of the chlo- 

 renchyma in the manufacture of carbohydrates, determinations 

 of the amounts of glucose present in the stem in the morning 

 and evening were made. During the same period a record was 

 kept of the transpiration and the results correlated. The 

 chemical analyses were made by Miss Long according to a 

 modification of the Munson-Walker method of testing for 

 glucose. 



(5) ADJUSTMENTS AND ADAPTATIONS 



The adjustments of a plant to the physical factors of its 

 habitat are most strikingly shown in the physiological responses 

 of growth and transpiration to light and to the water content of 

 the soil. To determine the effect of soil-water content upon 

 growth, Equisetum fluviatile was grown with roots submerged in 

 water, in mud, and in a soil-water content of 35%. All other 

 factors were kept uniform by using the same volume of the 

 same type of soil sifted through a 2 mm. screen. The plants 



