184 Transactions of the Society. 



If our modern philosophy of biology be, as we know it is, true, 

 then it must be very strong evidence indeed that would lead us to 

 conclude that the laws seen to be universal break down and cease 

 accurately to operate, where the objects become microscopic, and our 

 knowledge of them is by no means full, exhaustive, and clear. 



Moreover, looked at in the abstract, it is a little difficult to con- 

 ceive why there should be more uncertainty about the life-processes 

 of a group of lowly living things, than there should be about the 

 behaviour, in reaction, of a given group of molecules. 



The triumph of modern knowledge is a knowledge — which nothing 

 can shake — that nature's processes are immutable. The stability of 

 her processes, the precision of her action, and the universality of her 

 laws, are the basis of all science, to which biology forms no exception. 

 Once establish, by clear and unmistakable demonstration, the life- 

 history of an organism, and truly some change must have come over 

 nature as a whole, if that life-history be not the same to-morrow as 

 to-day ; and the same to one observer, in the same conditions, as to 

 another. 



No amount of paradox would induce us to believe that the com- 

 bining proportions of hydrogen and oxygen had altered in a specified 

 experimenter's hands in synthetically 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 you cannot 

 get abstract matter — that is, matter with no properties or modes of 

 motion — so you cannot 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 laws, which, by the way, could not operate at all if 

 caprice formed any part of the activities of nature. 



But let me give a practical instance of how what appears like fact 

 may override philosophy, if an incident, or even a group of incidents, 

 'per se. are to control our judgment. 



Eighteen years ago I was paying much attention to Vorticellaa. 

 I was observing with some pertinacity Vorticella convallaria — for one 

 of the calices was in a strange and semi-encysted state, while the re- 

 mainder were in full normal activity. I watched with great interest 

 and care, and have in my folio still the drawings made at the time. 

 The stalk carrying this individual calyx fell upon the branch of vege- 

 table matter to which the Vorticellan was attached, and the calyx 

 became perfectly globular, and at length there emerged from it a 

 small form, with which in this condition I was quite unfamiliar. It 



