
“MY WORK AND BACTERIOLOGY 307 
conversion of non-pathogenic into pathogenic organ- 
isms, we may well be’ surprised at his thinking 
that a process which he assumes to have occurred 
once in the days of the early Greeks, and before 
their time, may not be taking place now—as it may 
have done through all intervening periods of time. 
Like another eminent pathologist, however, he 
possibly inclines, for some mysterious reason, to 
the view that ‘the origin of the germs of disease 
was probably in the remote geological past.” 
What has just been said is equally applicable to 
the views of Dr Andrewes as expressed in his recent 
Horace Dobell Lecture (Zauce¢, Nov. 24) on “ The 
Evolution of the Streptococci.” Noting by the way 
that the bourne of Evolution is surely not parasitism, 
we find that what he speaks of is merely specialisa- 
tion. But to enable these primitive organisms to 
pass from the prototrophic to the metatrophic mode 
of nutrition he imagines incalculable periods of time 
to have been needed, and speaks of it as having 
been brought about through the agency of ‘“ natural 
selection.” Though how, in these non-nucleated 
organisms, natural selection is to act he does not 
venture to hint. Where, as here, chromosomes are 
absent heredity, according to current notions, would 
be impossible, and without heredity no “natural 
selection” could possibly come into operation. 
Of course the views referred to, which are very 
prevalent, are a kind of reflex of the notion that 
Archebiosis itself occurred, once only, in the remote 
past, and has not been repeated. Growing out 
of such a view there comes the notion that the 
