106 president's address — SECTION D. 



The young student in biology would think it almost incredible 

 that one who has not lived through two generations should be 

 able to recall from among the thoughts of adolescence the crude 

 conception of plant life which then lodged in his mind, undigested 

 by the pepsine of scholarly instruction as at that time imparted. 

 That plants had life of a kind appeared evident; they grew, mul- 

 tiplied, died, and decayed ; they even showed signs of irritability. 

 Yet it seemed little more than a metaphor, a concession to the 

 poverty of language, to speak of vegetables being endowed with 

 life such as other organisms possess. In this, as in most respects, 

 plants appeared to be as foreign in nature to animals as animals 

 obviously were to man. The times change and we change with 

 them, but the margin of a pool long remains unruffled by the waves 

 that creep from its disturbed centre. At the present day the 

 same traditional opinion in favor of the fundamental diversity of 

 life in the animal and vegetable realms would be professed by 

 numbers of reflective persons whose intellectual exercise has not 

 carried them within the pale of biology. It may then be asked of 

 us, Have you by searching foimd out anything to the point ? We 

 can answer in the affirmative ; it has long been established beyond 

 doubt that life in the plant and life in the animal, phenomenally 

 so discordant, are substantially one and the same. The steps by 

 which biology has mounted to this eminent conclusion — eminent 

 because from its height we can take a bird's eye view of life in all 

 directions — are Avorth recovmting. Their story will one day form 

 an interesting page in a history of knowdedge. 



For nearly 150 years there has been known a substance scattered 

 in minute masses through water, Avhere each particle discharges 

 on its own behalf every essential function of animal life — motion 

 through space, extension and retraction of parts, quest, selection, 

 ingestion and assimilation of food, circulation of fluids, secretion 

 and excretion, respiration, and reprodviction — in all these modes 

 of activity automatic, vet without definite organs or members, 

 without so much as a containin;^ investment. To us the creature 

 is partiall}' intelligible; but in 1755, the year of its discovery, 

 amoeba was a passage in the volume of life utterly undecipher- 

 able, and, as a cryptoijram teaching nothing, it was sufl^ered to lie . 

 for eighty years almost forgotten. Meanwhile the intimate struc- 

 ture of plants was being scrutinised by anatomical botanists, some 

 of whom found that the cells, which appeared to be the structural 

 elements into which all plant tissues could be resolved, were in 

 certain cases and circumstances capable of exhibiting automatic 

 movements. These observations also were impotent of results, but 

 lay as isolated facts, unincuhated till others were placed around 

 them, and all stimulated to find their way to light toeether. 

 Zoologists on their side had been pursuing a parallel path, and 

 had learned that animal tissue was structurally nothing more than 

 a system of cells. They now pushed the inquiry further, putting 



