ACQUIRED CHARACTERS 211 



innate capacity, tlie evidence seems to us to show, is the product 

 of evolution by the action of Natural Selection. Professor 

 Henslow, of course, may reply that there does not exist any such 

 unresponsive plant. But we think if he will appeal to known 

 facts, he will find plenty of evidence demonstrating the existence 

 of unresponsive plants. 



Let us illustrate the argument by an appeal to these facts. 

 The Sweet Woodruff is a British plant which lives in woods and 

 shady places. It is not imcommon, as an undergrowth, in some 

 beech forests. In such forests when thickly crowded, there is a 

 deep gloom or shade that would be fatal to other green plants. 

 But in this semi-darkness the WoodrufE thrives quite well. That 

 which is a harsh or fatal environment to other plants is to it a 

 necessity of its existence. Now, when for commercial reasons, 

 some of the beech trees are felled, and the forest is cleared in order 

 to let in more light and air, what happens to the woodruff ? If 

 Professor Henslow's contention is true that it is a universal pro- 

 perty of living protoplasm to respond to direct influences of a 

 changed environment, then the woodruff should adapt itself 

 to the new environment of a stronger light and more abundant 

 air, and survive under the changed conditions. But it does not. 

 It perishes. It is inherently unfit to survive these new conditions, 

 and it suffers elimination in consequence. It is the same with 

 the flax. It can live in the valleys, but if taken to the mountains, 

 where the light is stronger, it perishes. The plants now growing 

 in the desert of Kaits, in Ceylon, illustrate the same thing, but 

 more cogently. They have been living under desert conditions 

 for thousands of years, but yet they have acquired none of the 

 characters that belong to desert plants, except a compactness of 

 habit. They do not show sunken stomato, thick cuticle, and 

 succulent parenchyma. And the only desert peculiarity which 

 they possess, namely, their dwarf stature, as shown by Holter- 

 mann's observations, is lost when they are removed from the 

 desert and planted in garden soil. The influence of the desert 

 conditions has not changed the characters of these plants, for 

 they do not possess that combination of desert characters which 

 is the diagnostic quality of desert plants. 



These phenomena and the whole range of responses which 

 Professor Henslow adduces in his book, including M. Ph. Eber- 

 hart's experiments with woody stems, and Dr. Reid's statement 

 concerning the Kauri pines of New Zealand, seem to us to be but 

 different manifestations of the one thing, the inherent capacity 

 which most plants have of responding to their changing environ- 

 ment. But all plants do not possess this capacity in the same 

 degree or in the same way. It is a character which has been 



