420 



Dr. J. B. Farmer and Mr. S. E. Chandler. [May 6, 



Fig. 4. Impatiens platyphylla, transverse section of leaf. A, air-; B, C0 2 -plant. 



paper already referred to. No very satisfactory measurements were 

 made of these internodes with a view of ascertaining their relative 

 lengths, but in a general way the appearance presented by the two 

 series conformed to that already described for the other species. 



The proportionate size of the leaves in the two series was estimated 

 as 1-0 : 0-35. 



The numerical relation of the stomata per unit area of leaf in the 

 two cases is 1*0 : 1*4 (fig. 5, A and B), but the proportion of epidermal 

 cells to stomata in the two series respectively proved to be almost 

 identical, being 100 : 32 (air) and 100 : 31 (C0 2 ). 



