1917] 



DENN Y—PERMEA BILI T Y 



473 



had previously been 



remov 



Table V shows these results. 



perm 



tion, the decrease does not reach the low point exhibited by the 

 membrane before the original extraction. Apparently the lipoid 

 materials cannot be put back into the membrane in the condition 

 and position in which they existed before extraction. This would 

 indicate an organized distribution of these materials in the mem- 

 branes in nature. 



TABLE V 





Effect 



OF INFILTl 



RATING MEMBRANES 







Membrane 



Area in sq. 

 mm. 



Concen- 

 tration of 

 solution 



Rate before 

 extraction 



Rate after 



extraction 



with hot 



acetone 



Rate after 



extraction 



with cold 



acetone 



Rate after 



infiltration 



with lipoid 



extract 



Peanut 



SO. 265 

 '9-63S 



a 

 a 



50. 265 



U 



0.5 M 

 Saturated 



u 



u 



u 



65-71 



24.27 



4.08 



16.17 



IOI. 10 



121.34 





246 . 68 



76.84 



181.98 



30.33 

 84.92 



4246 

 232.52 



258.81 



u 





Pumpkin 



146.26 



54-59 

 298. 26 



326.03 



Cocklebur 





Almond. . . 





u 







Effect of extracting membranes with calcium chloride 



The calcium ion has been shown by Hansteen-Crannter (2) 

 to reduce the rate of water intake by the cell walls of roots, and it 



um 



effects upon the permeability of seed coats to water. Membranes 

 were selected and measurements made of their permeability to water ; 

 these membranes were then soaked for 24 hours in calcium chloride 

 solutions of the concentrations described later; the membranes 

 were then rinsed in distilled water, placed in the osmometer, and 



meability 



Table VI shows the results. 



It thus seems that calcium chloride at the concentrations used 



permeability 



Whether 



similar 



et to be determined. 

 The fact that callose 



cium 



perm 



to the extraction of callose from the membrane. No micro- 

 chemical differences were noted in membranes before and after 



