DOES SILICON REPLACE CARBON? 113 



then as now, though their relative proportions 

 differed slightly. 



In the intervening period the same suggestion as 

 to silicon being able to replace carbon in organic 

 compounds has been made by others, including 

 Clemence Rover, Alfonso Herrera of Mexico, 

 Georges Renaudet, as well as Albert and Alex- 

 andre Mary. 1 It is, of course, well known to enter 

 largely into the structure of the stems of grasses, 

 bamboos, equisetums, and other plants. 



Apart from these general considerations, there 

 are the following special facts in reference to the 

 foregoing experiments made with ingredients 

 namely, sodium silicate, ammonium phosphate, 

 dilute phosphoric acid, and liquor ferri pernitratis 

 nominally containing no carbon, though CO 2 

 would be contained in the distilled water and in 

 the air above the solutions, while carbon would 

 also very probably exist as an impurity in the 

 sodium silicate itself. 



Still, if we bear in mind the following facts, it 

 seems probable that there has been a partial sub- 

 stitution of silicon for carbon in the constitution 

 of the organisms found: 



1 See the work of these latter writers entitled Evolution et 

 Transformisme (Paris), tome iv., 1910, pp. 306-315. 



