Walter Stiles 
146 
ion concentration greatly influences the intake of cyanol and orange 
G by perianth leaves of Hyacinthus, the intake being furthered by 
acidity and reduced by alkalinity. A 0*25 to 0-2 per cent, solution 
of ammonium carbonate completely prevented the intake of cyanol 
and orange G. These results fall into line with those of Harvey (1911) 
and Endler (1912 b) who found the reverse influence of acidity and 
alkalinity on the penetration of basic dyes. It is not clear how far 
these results are connected with the general phenomena of antago¬ 
nism. 
Sziics (1910) found that the rate of intake of a basic dye, methyl 
violet, or neutral red, is much reduced in presence of the acid dye 
congo red. This is attributed to the formation of a compound of the 
two dyes in the external solution: a compound which cannot enter 
the cell. The non-entrance of the dyes in such cases is obviously not 
comparable with the other cases already discussed. 
Methods of making quantitative determinations of antagonism 
by comparing amount of growth in plants in different solutions under 
otherwise the same conditions, have been formulated by Osterhout 
(1914 b,c,d). While such methods are undoubtedly of importance 
from the point of view of the study of growth, they do not provide 
a means of determining intake or permeability under different con¬ 
ditions of composition of the external solution. One point of importance 
emphasized by Osterhout (1914 d) to which reference may be made 
is that the relative concentration of two salts in which antagonism is 
greatest is not affected by dilution or concentration of the mixed 
solution. This is certainly an important fact, but to state that this 
law of direct proportionality “is in reality Weber's law" (Osterhout, 
1916 c) appears to me an unwarranted extension of the scope of 
Weber’s law 1 . 
Exact quantitative data relating to the influence of one substance 
on the intake of another are for the most part wanting. The best 
available appear to be those of Sziics on the intake of methyl violet 
in presence of various inorganic salts; these experiments have already 
been described. It will be necessary to obtain a vast quantity of 
further data before Sziics' view that antagonism in this case results 
from adsorption of the inorganic salts by the protoplasm can be 
accepted, especially as Endler’s experiments on the intake of methy- 
1 “Weber’s law states that ‘the just noticeable increase of a stimulus bears 
a constant ratio to the original stimulus,’ or ‘two stimuli, in order to be dis¬ 
criminated, must be in a constant ratio, the latter being independent of the 
absolute magnitudes of the stimuli.”’ (Flack and Hill, 1919.) 
