50 TKANSACTIONS AND PROCEEDINGS OF THK [Se.ss. lxv. 



assimilated and reproduced ; it is nourished at the expense 

 of substances different from itself, as is the case with the 

 micrococci and other organisms. 



So the primitive molecule, which constituted the micro- 

 coccus, has undergone a series of special chemical changes 

 until a phase is reached when it contains double its original 

 number of atoms, whereupon it splits into two daughter 

 molecules, each with the same number of atoms as the 

 mother had at the beginning. If a indicates the constitution 

 of the molecule at the instant of its birth, its new con- 

 stitution, after a series of chemical changes, at the instant 

 of cUdouUement may be represented by M. The life 

 cycle of the molecule may be diagrammatically represented 

 as under — 



a . . M = a -\- a 



Two phenomena are noticeable here — 



(1) A doubling of the primitive molecule a, which has 

 been transformed into M, i.e. into two other molecules, a a. 

 This is a true re^jrodudion. 



(2) A transformation of the molecule a into J/, by a 

 series of chemical changes, during which molecule a has 

 doubled the number of its atoms. This is assimilation, of 

 which reproduction is the end result. 



The author regards this analogy between the chemical 

 phenomena of the methyl-ethyl-ketone molecule and the 

 vital phenomena of the micrococcus as perfect, and con- 

 cludes, therefore, that, on ultimate analysis, assimilation 

 and reproduction are chemical phenomena. 



Since these phenomena can be artificially induced among 

 dead chemical substances, why suppose a special force 

 necessary to explain them ? The action of chemical affinity, 

 which produces chemical changes in dead matter, suffices of 

 itself to give an explanation. 



To the query of why, if capable of assimilation and 

 reproduction, is the molecule of methyl-ethyl-ketone not 

 living ? the answer is given that the conditions of its 

 existence are not realised, or not realisable, in nature. 

 From the study of the artificial life of this molecule, the 

 necessary conditions of life for a living molecule (biomole- 

 cule) are deduced, i.e. the conditions necessary for the 



