EVOLUTION 167 



nothing as to their mode of action. The Darwinian theory 

 shows how acquired variations are transmitted and accentuated 

 hy natural selection, but it says nothing as to how these varia- 

 tions may be acquired. In the same way we are in entire 

 ignorance as to the physical mechanism of ontogenetic develop- 

 ment, the evolution of the embryo. 



The morphogenic action of diffusion produces osmotic 

 growths of extreme variety. Most of these forms recall those 

 of living things- -shells, fungi, corals, and algae. The analogy 

 of function is quite as close as the resemblance of form. The 

 study of osmosis, however, is as yet in its infancy, and osmotic 

 productions vary with the physical conditions of chemical 

 constitution, temperature, concentration, and the like. The 

 study of the organizing action of osmosis on organic material 

 has as yet been hardly attempted. 



Osmosis produces growths of great complexity, much more 

 complicated indeed than the more simple forms of living 

 organisms. This marvellous complexity of an osmotic growth 

 may be compared with another fact, the ontogenetic develop- 

 ment of the ovum, a single cell which under favourable 

 conditions of environment may evolve into a most complicated 

 organism. These considerations lead to the belief that the 

 beginning of life has not been the production of a simple 

 primitive form from which all others are descended, but that 

 a number of such primitive forms may have been produced, 

 forms which by a rapid physical development attained a high 

 degree of complexity. Osmotic morphogenesis shows us that 

 the ordinary physical forces have in fact a power of organiza- 

 tion infinitely greater than has been hitherto supposed by the 

 boldest imagination. 



When we consider the ignorance in which we still remain 

 as to the phenomena which pass before our very eyes, how can 

 we expect to understand those which occurred in past ages, 

 when the physical and chemical conditions were so immensely 

 different from those which obtain in our own time? What do 

 we know even now of the physical and chemical phenomena 

 which take place in the unfathomed depths of the ocean, 

 where for aught we know even at the present time the same 



