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healthy blood cells and unhealthy germs which takes place in the 
diphtheritic membrance. He shows that the diphtheritic microbes, 
which are present in enormous numbers in the superficial layer of 
the false membrane, are hardly discernible in the succeding layers, 
and are entirely absent from the lowest layers of the false 
membrane. Moreover, many of the ameboid cells or leucocytes in 
the layer of the false membrane immediately below the superficial - 
layer are seen to contain two or more of the diphtheritic bacilli 
which they have evidently attacked and partly destroyed. Dr. 
Ruffer adds, “the diphtheritic membrane is a battle-field. for 
amoeboid cells and the pathogenic microbes of diphtheria. The 
reason why the bacilli do not penetrate into the tissues is probably 
that as soon as they do so, they are arrested by the ameboid cells 
present in the diphtheritic membrane.” Dr. Ruffer confirms the 
opinion of many eminent bacteriologists, that a constant warfare 
is ever taking place within us, between healthy cells and unhealthy 
germs, and just in proportion to our health and vigour, are we able 
to resist and overcome these insidious foes. 
Not animals but plants are attacked by these parasitic fungi, 
and the “blight,” « mildew,” and mould,” with which we are all 
familiar, and with which plants are so often affected, are all due to 
the depressing agency of some specific micro-organism. Professor 
Soraner, who is an authority on the diseases of plants, ascribes the 
potato blight which was so prevalent last autumn to a bacterium 
termed “‘clostriplum batyricum ” (which you see depicted on this 
diagram). This germ “is able to dissolve the cell walls (of 
the potatoe), and to develop butyric acid” ; if the diseased tubers 
“are at once put into a dry, light place, the vegetation of the 
bacteria is arrested,” but is left unexposed to the air, “ the potatoe 
will rot away into a thin, dirty liquid, held together by the skin.” 
Here again is a proof of microbes flourishing in darkness and in 
damp, but withering away if exposed to the beneficent rays of the 
sun. 
We hear and read so much of the disastrous influence of germs 
that we scarcely realise the inestimable service rendered by bacteria 
in changing and removing the products of decay and death. They 
literally regenerate the world by devouring the debris of dead 
organic matter, and reducing it by decomposition, into its original 
_ harmless components. Were it not for their salutary influence in 
revolving all dead and putrescent materials into their original 
elements, the world would long ago have become one vast charnel 
house, unfit for human abode. Indeed, life itself would have 
become impossible were it not for their agency, for the whole 
surface of the earth would be filled with the noxious remains of 
every type of organic matter, both animal and vegetable. Hence 
