The President's Address. By the Bev. W. H. Ballinger. 191 



studied in detail, presents results tliat may not be without interest to 

 this Society, even in an Annual Address. 



The observations I refer to were made with a view to discovering 

 whether it was possible by change of environment, in minute life- forms, 

 whose life-cycle was relatively soon completed, to superinduce changes 

 of an adaptive character, if the observations extended over a sufficiently 

 long period. 



For such observations it is manifest that the lowest forms of the 

 infusoria offer suitable subjects. 



In themselves and taken by themselves, these organisms, under such 

 experiment must afford instruction, if we can obtain results. But it is 

 also of interest to remember that the inference that the higher and more 

 complex animals and plants are vast aggregations of cells differently 

 endowed in different parts of the organism, but all functionally united 

 and correlated to secure the life of the living thing they compose, is^ an 

 admitted fact in biology. This must add, indirectly, a further interest 

 to the subject. 



Few biologists need any direct demonstration to convince them of the 

 truth of Darwin's great law of the origin of species. It underlies as a 

 necessity all our widest and deepest biological knowledge. Concurrent 

 adaptation to concurrent changes of environment is in fact so apparent 

 now, that we wonder, often, why it was not earlier seen. 



Nevertheless, if it be possible to look upon the progress of changes 

 in minute living organisms, superinduced by elected changes of environ- 

 ment, however simple, and which results in morphological and physio- 

 logical adaptations and survivals, it cannot be other than a gain both to 

 philosophical and practical biology. 



Before actually setting up a definite line of procedure, I spent a year 

 and a half in tentative experiment ; and very soon found that the best 

 subjects for my research would be the monad forms I had become so 

 familiar with, and the phases of whose life-history I knew ; and that 

 •the best and most amenable agent I could use for altering slowly and 

 cumulatively the environment, was heat. 



After the year and a half of trial I obtained certain very definite 

 results, which it appeared to me pointed to the possibility of obtaining 

 others of a far higher meaning and value, if the methods of conducting 

 the inquiry were carefully devised, and for an indefinite time con- 

 tinuously operative. 



At this time I was closely tied to a provincial town, and had little 

 opportunity for consultation with leading men of science ; but amongst 

 the few who influenced my determination was the late Chas. Darwin. 

 He had shown great interest, and given me great encouragement in 

 prosecuting the life-histories ; and in correspondence, amongst other 

 things, I gave him details of the imperfect but still interesting results 

 I had obtained by thermal experiments on these forms, and the pre- 

 , parations I was making for systematic inquiry in that direction. After 

 words all too generous, he said in his reply, which was dated July 2nd, 

 1878, " I did not know that you were attending to the mutation of the 

 lower organisms under changed conditions of life ; and your results, 

 I have no doubt, will be extremely curious and valuable. The fact 



