376 Philosophy of Botany. 



shapeless and formless ferments, which, like yeast — a well- 

 known orgfanized ferment — excite fermentation in orgTanic 

 solutions and cause the splitting up of their molecular struc- 

 ture, without experiencing an increase of their own volume. 

 By this they imitate or replace the vital action of the formed 

 fermenters. 



Judging from the ordinary standard those shapeless bodies 

 would be considered as lifeless; yet it ^is very doubtful if 

 they should as such be held, for they develop properties in 

 common with those of the living ferments. Whenever the 

 solutions of these enzymes are exposed to temperatures of 

 160° to 210° they become inefHcient just as well as the organ- 

 ized ferments. They are also killed by alcohol, corrosive sub- 

 limate, and all the substances which destroy the vitality of 

 the bacteria. Thus is established a difiference between living 

 and dead enzymes. 



Recently an experiment was made by Buchner, to obtain 

 under high pressure a juice from living ferment-organisms, 

 with subsequent filtration. The fluid prepared in this way 

 has had the same effect, like the living structural ferments. 



Thus we are led to conjecture a still lower grade of vital 

 processes, some kind of chemical life which eludes our micro- 

 scopical investigations. 



The immense quantities of carbon now deposited in the 

 devonian and carboniferous strata and the oil-soaked lime- 

 stones and sandstones of the Silurian, circulated as carbonic 

 dioxide, mixed with sulphureted hydrogen gas. Immense 

 periods may have passed before the rays of the sun broke 

 through the clouds, before chlorophyll-bearing tissues could 

 proceed to depurate the air of the carbon. The geometric reg- 

 ularity of the organic forms of that era, the protophytae 

 (diatomacese and cosmariacese) , and of the protozoa (radi- 

 olarisR) and the large percentage of mineral matter, silica, 

 and carbonate of lime, contained in their texture, give them a 

 great resemblance to certain systems of crystallization — snow- 

 flakes or augitic forms of crystals. 



The doctrine of protoplasm as advanced by Huxley and 

 the recent success in synthetic chemistry in the production of 

 some organic compounds, like urea or indigo, hold out the 



