314 DR. WILLIAM ROBERTS. 



The development of bacteria in hay-infusion, after having 

 been boiled continuously for several hours in hermetically 

 sealed vessels, seemed to furnish the very strongest attain- 

 able evidence in favour of the abiogenic origin of these 

 organisms ; and yet, by a singular fatality, the investigations 

 of Cohn have shown that this evidence, rightly interpreted, 

 supplies a crowning argument against that view. 



Cohn had the curiosity to examine the organisms which 

 arose under these extraordinary circumstances. Did he find 

 a new birth? On the contrary, he recognised a familiar form; 

 none other than our old acquaintance the Bacillus suhtilis. 

 He followed it through all the stages of its development. It 

 first appeared some twenty-four hours after the boiling, in 

 the form of innumerable short moving rods. On the second 

 day, these rods shot out into long threads ; on the third day, 

 there appeared on the threads, at perfectly regular intervals, 

 strongly refractive oval bodies, which he identified as spores. 

 Finally, the threads broke down and the spores were set free. 

 In many hundred observations, he saw this one organism and 

 no other, and witnessed the successive stages of its develop- 

 ment occurring with the constancy of a physical experiment. 



Now, let me ask if this looks like an act of abiogenesis. 

 The evolutionist demands, for the transformation of one 

 organic type into its next descendant, myriads of genera- 

 tions, and I know not what lapse of ages. But here, if this 

 be a case of abiogenesis, we see accomplished at one leap, in 

 a single generation, and in seventy hours, not merely the 

 bridging over of the gulf between the dead and the living, 

 but the development of a specifically distinct organism, with 

 definite form, dimensions, and mode of growth, and furnished 

 with a complete provision for the reproduction of the species ! 

 I need scarcely say that such a feat would be, not only 

 without parallel in the history of evolution, but would be 

 wholly contradictory to that theory. 



The only group of bacteria, so far as is known, which form 

 spores are the Bacilli ; and Cohn remarks that in all the 

 various cases in which he had observed organisms to arise 

 in boiled liquids, they belonged in every instante to the 

 Bacilli. 



Before leaving this part of my subject, I wish to suggest 

 certain considerations in regard to the nutrition and func- 

 tion of saprophytes, which appear to me to render it in 

 the highest degree improbable that spontaneous generation 

 should ever be discovered in this quarter. If it be assumed 

 that the occurrence of abiogenesis, at some time in the past 

 history of the globe, is a necessary postulate in science, and 



