394 True and Hunkel, Tlie Poisouous Efl'ect Exerted etc. 



From the accompanying table, guaiacol is an activc poison 

 to lupines, tlie niost concentrated Solution allowing growth being 

 tliat containing 1/800 gram-raolecule per liter. being, therefore, 

 more strongly toxic than anisol. It will be observed that here, 

 as in tlie case of anisol, the ether Las the sarae toxic value as 

 the phenol from Avhich it may be regarded as derived by replacing 

 the H of an OH group with the CHs group. 



Spirogyra filaments give results differing somewhat from tliose 

 obtained with the lupines. As in the casc of anisol, the alga is more toler- 

 ant toward the Compound than are the lupines, the lirst Solution in which 

 majority of the tilaments survivcd being 1/150 to 1/200 gram-molecule 

 per liter. This is a stronger Solution than the alga was able to with- 

 stand in the case of anisol, thus reversing the relative positions 

 in the scale of toxicity as seen for the lupines. 



Salicylic acid, Cc Hi (011) (COOH) = 1 : 2, is botli an acid 

 and a phenol in its Constitution, but the acid characteristics give 

 it its most pronouneed properties. The toxic value of salicylic 

 acid has been determined by Kahlen berg and True.^) The 

 concentration lirst permitting lupines to survive was found in a 

 Solution containing 1/6400 gram-molecule per liter, the boundary 

 observed, generaily, for monobasic acids undergoing completc 

 dissociation. Ostwald^) has shoAvn that at the much stronger 

 concentration of one gram-molecule in 1024 liters this acid disso- 

 ciates 62,80 per cent. A materially grcater degree of dissociation 

 might be expected in the dilutions here used. 



r t h o - o X y b e n z o i c acid, salicylic acid, Ce Hi (OH) 

 (COOH) = 1:2. Boundary - concentration, 1/6400 gram-mole- 

 cule per liter. 



Table XLI. 



1) Kall Jen berg aud Tru(>. Bot. Ü a z. XXII. p. 120. and MSS. 

 results not yet published. 



') Ostwald, W., Zeitschrift für physik. Chemie. Band II. 



