72 



tilled water. About 600 cubic centimeters of the Hui:)ernatant solution 

 was then decanted through a folded filter, and the analytical details 

 carried out with 100 cubic centimeter portions of the filtered liquid. 

 It was thought probable that this procedure would give a close approxi- 

 mation to the soluble salts on the plant or held in its tissues in the 

 form of inorganic salts. The acid material on the surface of the i3lant 

 was evidently quite soluble in water. It was concluded, as Avill be 

 shown later, that it was an organic acid, and that in all probabilit}^ 

 considerable quantities of its sodium or other salts, as well as the acid 

 itself, were on the surface of the plant and dissolved in the water. 

 The amount of free acid was determined b}" titrating with a solution 

 of potassium hydroxide, which in turn had been carefully standard- 

 ized b}' titration against a twentieth normal (N/20) solution of acid 

 potassium sulphate. The other determinations were made in the con- 

 ventional way. 



DISTICHLIS SPICATA. 

 Table XYL—Distichlis spicata. 



Grams of material 



Cubic centimeters of leachiugs 



Percentage (mineral matter) leached 

 out 



Cubic centimeters N/20 acid equiva- 

 lent to 1 gram substance 



Ca 



Mg 



Na - - - 



k: 



S04 - 



CI - 



CaS04 



CaClo 



MgCl, 



KCl -- 



NaCl 



Na 



Sample I. 



Sample II. 



13.12 



750 



4.53 

 33. 03 



35. 35 



1,350 



5.13 

 1.16 



Samule III. 



39.48 

 1.500 



5.73 

 3.48 



Percent- 

 age dis 

 tribu- 

 tion. 



5.63 



1.86 



41.30 



13.40 



4.38 



33.44 



100. 00 



6.19 

 10.48 



7.25 

 25. 52 

 15.22 

 35.34 



100. 00 



Percent Percent- 

 in air- age dis- 

 dried ; ti-ibu- 



material.i tion. 



0.254 

 .084 



1.867 

 .606 

 .198 



1.511 



4.520 



.474 



.328 

 1.154 



.688 

 1.598 



4.520 



1.17 



33.12 



9. 70 



4.69 



48.43 



100.00 



6.64 



2.58 

 4.57 

 18.49 

 57.08 

 10.64 



100.00 



Per cent 

 in air- 

 dried 



material. 



Percent- 

 age dis- 

 tribu- 

 tion. 



0.148 

 .060 



1.696 

 .497 

 .240 



5.120 



.340 

 .132 

 .234 

 .947 

 3.923 

 .545 



5.120 



3.25 

 2.10 

 27.24 

 12.23 

 2.72 

 52.46 



100. 00 



3.83 

 5.90 

 8.20 

 23.27 

 52.03 

 6.77 



100.00 



Per cent 

 in air- 

 dried 



material. 



0.186 

 .120 



1.561 

 .701 

 .156 



3.006 



.219 

 .338 

 .470 

 1.333 

 2. 981 

 .388 



5.730 



Table XVII. — Soil {0-12 inches) in 2chich Sample I of Distichlis spicata loas found. 





Per cent. 





Per cent. 



Ca 



0.48 



.16 



33.77 



1.81 



5.44 



8.06' 



22.63 



27. 65 



CaS04 - -.- 



1.60 



Mg.,. 



MgS04 - - 



.75 



nI 



Na.>S04 



5.50 



K . 



KCl 



3.47 



SO4 



NaCl - 



NasCOg - --- 



10.73 



CI.. "... : ' 



39.96 



CO3 



NaHCOs - -- 



38.00 



HCO3 



Percentage soluble, 1 gram soil to 20 







100 00 





100. 00 



3.75 









