456 PHYSIOLOGY OF THE INVERTEBRATA. 



producing water. We believe that the melting-point of 

 platinum and the freezing-point of mercury are the same as 

 they were a hundred years ago, and as they will be a 

 hundred years hence. Now carefully remember that, so far 

 as we can see at all, it must be so with life. Life inheres in 

 protoplasm ; but just as one cannot get ahstract matter — that 

 is, matter with no properties or modes of motion — so one 

 cannot," says Dr. Dallinger, " get abstract protoplasm. 

 Every piece of living protoplasm we see has a history : it 

 is the inheritor of countless millions of years. Its properties 

 have been determined by its history. It is the protoplasm 

 of some definite form of life which has inherited its specific 

 history. It can be no more false to that inheritance than an 

 atom of oxygen can be false to its properties. All this, of 

 course, within the lines of the great secular processes 

 of the Darwinian law, which could not operate at all if 

 caprice formed any part of the activities of Nature." 



In addition it may be remarked that pleomorphism is 

 entirely opposite to the Darwinian law, but abiogenesis (as 

 already stated at the commencement of the present chapter) 

 is not' in opposition to evolution. It is one of the theories 

 which have been brought forward to explain the origin of life 

 in the world. Protoplasm consists of carbon, hydrogen, 

 oxygen, nitrogen, with a little sulphur and phosphorus, and 

 still fainter traces of other elements, combined in extreme 

 complexity. " Given the matter which composes it, and the 

 play of forces and energies of which that matter is the 

 vehicle, wherein lies the difference which gives as one result 

 non-living substance, and as another result living substance ? 

 The answer obviously is that, the ingredients being the same, 

 the difference must lie in the mixing ; " and it is this 

 "mixing" which the scientist has to find out to explain the 

 origin of life, or, before abiogenesis can be considered to be 

 more than one of the theories which have been put forth 

 during historic times to account for it. 



