258 The Idea of Evolution. 



what Darwin gave, and might he put down as harmony with 

 environment. Every plant and every animal living to-day was 

 adjusted more or less exactly to its conditions at that particular 

 place and in that particular era. If they examined the com- 

 monest plant and looked at the shapes of the leaves, the teeth, 

 and hairs on leaves, and then studied the conditions in which 

 \ou found them growing, you would find that every one of these 

 minute details were of real importance to its life. It was on 

 these little adaptations by which the plant or animal came into 

 the most perfect harmony with all the needs of its special 

 atmosphere that he thought a great prospect lay for British 

 botanists. Good hooks had been published on the subject by Sir 

 John Lubbock and Kerner, and others ; but so far he found in 

 this country that people will not take up these interesting and 

 important subjects, but preferred to spend their time on purely 

 systematic work. The study of plants which were avoided or 

 preferred by animals was a very important one, and we know 

 nothing about it. Again, we do not understand much with 

 regard to the scattering of fruit and seed, and a whole infinitude 

 of subjects are not studied at all. The next development is of 

 the nature of a denial. The inheritance of acquired characters 

 was denied by Dr Weissmann, a German, who, however, brought 

 forward no evidence except his opinion that it could not be true, 

 because it interfered with his theory of heredity. That was 

 scarcely scientific reasoning, and it was soon pointed out that 

 if you denied the fact that a character acquired in life could be 

 inherited it led you into very curious positions. For example, 

 dipsomania could certainly be acquired, but according to 

 Weissmann it could not be inherited. That criticism was got 

 over, and with very great advantage to science, but its effect 

 had been unfortunate, as it prevented a great many people from 

 following up what seemed to be a very valuable field of inquir}-. 

 The next point was the struggle for life within the body of the 

 plant or animal. Such an organ as one's hand or the foot of 

 a horse was composed of an infinite number of little living 

 particles. It had been pointed out by the German botanist, 

 Rolfe, that these living cells or particles were competing for 

 food with one another, so that if you used your thumb, and if 

 the same amount of blood was passing into your hand, the 

 excessive use of the thumb would dwarf the little finger or 



