DEPARTMENT OF BOTANICAL RESEARCH. 53 



seen to increase the hydration swelling, water-capacity, or water-deficit 

 of agar, agar-soap, agar-gelatine, agar-gelatine salts, and gelatine, 

 but to lessen hydration in some biocoUoids containing soaps which 

 would be sensitive to the free hydrogen ions of the vitamin solution. 

 Parallel action in living and dead cells is implied, although it is to be 

 noted that such cells may ah-eady include a certain amount of their 

 characteristic vitamins and that the added vitamin could exert no 

 additional effect except tha,t of reducmg hydration capacity. The 

 theory as to the constitution of living matter by which plant proto- 

 plasm is taken to be a pentosan-albumin-soap colloidal mixture has 

 been found adequate in such experiments. 



The metals which form the bases of nutrient salts of plants, as 

 chlorides and nitrates, are found to increase the hydration capacity 

 or the water-deficit of the principal components of biocolloids and of 

 biocolloids of certain composition. 



Biocolloids containing soaps show a high degree of sensitiveness to 

 hydrogen ions or acidity. Such biocolloids show marked action in 

 balanced solutions of sodium and calcium, as shown by data too de- 

 tailed to be given in this paper. 



Water-soluble B-yeast vitamin in a solution sHghtly acid increases 

 the sYv^elling, hydration, or water-deficit in some living and dead plant 

 cell-masses and lessens it in others. Similar diverse action on biocol- 

 loids was found. 



All of the substances tested which are known to facilitate growth in 

 plants are found to increase hydration capacity or water-deficit in some 

 of the test objects. The list includes chlorides and nitrates of sodium, 

 potassium, magnesium, and calcium in various concentrations between 

 O.OOIn and O.OOOIn, glycocoU, alanine, phenylalanine, histidine, and 

 water-soluble B-yeast vitamin. Hydroxides of sodium, potassium, 

 lithium, rubidium, calcium, ammonium, and aniline also increase 

 hydration values in some components of living matter. 



The Action of Bases and Salts on Biocolloids and Cell-Masses, by 

 D. T. MacDougal. 



The suggestion was made in an earlier paper that the common metals 

 which enter into nutrient solutions might find their chief importance 

 in restricting, limiting, or defining hydration of the cell-colloids. 

 MacDougal and Spoehr carried out a series of tests upon this matter 

 and found that the strong metallic bases when used at concentrations 

 of O.OIn do limit or restrict the hydration of agar according to their 

 place in the electromotive series, the least swelling taking place under 

 the action of the strongest base, with rubidium unplaced. Beginning 

 with the strongest, the series runs K, (Rb), Na, Li, and if calcium were 

 added to the series the swelling under its action was less than tliat in 

 potassium. When the concentrations were reduced, however, to 



