552 
PIERRE A. FISH. 
cell wall naturally retards the passage of oxygen. If the cell 
be surrounded by a layer of some inert substance oxidation is 
also restrained. The closer the contact of the protoplasm of the 
cell with the fluid containing the oxygen, the more easily will 
oxidation occur. 
The conditions just described for the somatic cell would 
seem to hold with equal force for certain of the bacteria. With 
these organisms we get, perhaps, a greater variety of limiting 
cell membranes than in the cells of the tissues. Differences in 
thickness, and perhaps of structure, so that with some at least, 
oxidation of the protoplasmic substance of the organism is not 
easily effected. Moreover the medium surrounding the germs 
may vary greatly with respect to its oxygen-carrying power. 
Guinard (3a) cites three principal modes of action of anti¬ 
septics : 1st. The action upon the germs themselves. 2d. The 
action upon the poisons, toxins or soluble products secreted by 
the germs. 3d. By modifying the medium upon which they 
grow, i. e ., action upon the tissues or organic liquids. 
Under the first heading, antiseptics may act: as an im¬ 
mediate deadly poison or as an obstacle to the development of 
the microbes, or preventing the secretion of their toxins. The 
antiseptic may kill the micro-organism by oxidation or coagula¬ 
tion of its protoplasm with the formation of an insoluble com¬ 
pound where life cannot be restored (Duclaux). The antisep¬ 
tic may manifest only a paralyzing action which hinders the 
development of the germs. This action does not, ordinarily, 
prevent the organisms from inhabiting a new place and becom¬ 
ing active there, they have been rendered only temporarily 
inert (Duclaux). 
Furthermore when an antiseptic is not able to suspend the 
multiplication of a micro-organism, it is often capable of pro¬ 
foundly modifying its morphology, the bacillus pyocyaneus 
takes on different forms, often unrecognizable, in contact with 
antiseptics (Cliarrin and Guignard). Cultivated in bouillon 
acidulated with tartaric acid the Micrococcus prodigiosus takes 
a bacillus-like form (Wasserzug). 
