A livi 
THE 
AMERICAN NATURALIST. 
VoL. xiv. — APRIL, 1880. — No. 4. 
PROTOPLASMIC DYNAMICS. 
BY PROF. W. S. BARNARD, PH.D. 
tes present general tendency of natural science is. towards 
unification. Formerly it was truly “ natural history,” analyti- 
cally descriptive and distinctive, while morphological classifica- 
tions were formed on external resemblances known as analogies, 
or on interna! structural analogies entitled homologies. But this 
stage of culture has passed its maturity, while the investigation 
of processes has introduced the natural, synthetic, explanatory 
stage, with its abundant results now appearing. 
The derivation of the physical forces from each other by trans- 
mutation, and from chemical and mechanical actions, which they 
are capable of originating again, the development of organisms 
from protoplasm, a substance, which, with its functions, all have 
in common, and the doctrine of the evolution of species, present 
- only some of the most important advances made toward a unita- 
rian system combining all objects and operations together as they 
are derived from each other. While some chemists expect that 
Organic chemical combinations may yet be obtained by uniting 
inorganic molecules in the laboratory as in the bodies of plants, 
carbon ebrtigiounids, the physiologists have decided that there are 
chemical. changes and physical forces associated with, and seem- 
ing to have a causal connection with, the production of organic 
Powers and functions. But there can be no positive certainty es 
this transition unless we can show how and why it necessarily — Z 
o RA: To effect this and to ene to trace c eea the : 
: ms Vhs HAV. ry, 16 à 
and thetic are those who think with Haeckel that the very lowest . 
may arise by sp generation from the higher 
