INTRODUCTION Xvii 

have once entered into the constitution of living 
things, it is now, in the ordinary acceptation of the 
term, dead matter—just as much as the matter con- 
tained in an ammoniacal saline solution is dead 
matter. It is true that the molecules in the organic 
solution are much more complex, and that, on this 
account, it might reasonably enough be considered 
to be a more easy process to bring about a new life- 
origination therein than in a more simple saline 
solution. The principal lesson that we may learn 
from such a fact would be, that the process of 
Archebiosis, which so many believe to have un- 
doubtedly occurred in the past (when hitherto there 
had been no living thing on the face of the earth) 
ought to be much more easy of occurrence in the 
present day when organic matter in solution is so 
widespread over its surface. 
The foregoing views, and the radical distinction 
between the processes of Archebiosis and of Hetero- 
genesis, may perhaps be more fully brought home 
to the reader by the following table reproduced 
from my work, ‘The Beginnings of Life.” 



ARCHEBIOSIS From not-living materials, 
(primordial 
origination). [ f 1. From a portion of the liv- 
ing matter of a pre-existing 
organism—(a) after its death ; 
(2) before its death. 
Heterogenetic, 4 2: By a molecular metamor- 
ene phosis of the matter of an entire 
re REPRODUCTION BESS Rion: : 
iis (from pre-existing J : 3. By aes metamorphosis and 
THINGS living things). fusion of many minute organ- 
isms. 
{ 1. Indirect. Cases of ‘‘alter- 
: nate’’ or cyclical generation. 
Homogenetic. 2. Direct. Continuous de- 
| velopment into the likeness of 
\ 
its parent. 
