260 THE WORLD OF LIFE chap. 



have fresh descendants, and of these only the very best, the 

 most gifted naturally, would survive. The increased adapta- 

 tion during the life of the individual would not be trans- 

 mitted, but the quality of being improvable during life would 

 be transmitted, and thus additional time and a considerably 

 increased population would give more materials for natural 

 selection to act upon. With this help the species might 

 become so rapidly improved that the danger from the new 

 environment would be overcome, and a new type might be 

 produced which would continue to be a dominant one under 

 the new conditions. 1 



Now, while it must be admitted, that under certain 

 conditions, and with certain classes of adaptations, the 

 normal effects of natural selection would be facilitated by 

 the aid of individual adaptation through use of organs, yet 

 its effect is greatly limited by the fact that it will not apply 

 to several classes of adaptations which are quite unaffected 

 by use or exercise. Such are the colours of innumerable 

 species, which are in the highest degree adaptive, either as 

 protecting them from enemies, as a warning of hidden 

 danger (stings, etc.), as recognition -marks for young or for 

 wanderers, or by mimicry of protected groups. Here the use 

 is simply being seen or not seen, neither of which can 

 affect the colour of the object. Again, nothing is more vitally 

 important to many animals than the form, size, and structure 



1 As many readers are ignorant of the extreme adaptability of many parts of i 

 the body, not only during an individual life, but in a much shorter period, I will ; «;e 

 here give an illustrative fact. A friend of mine was the resident physician of a 

 large county lunatic asylum. During his rounds one morning, attended by one 

 of his assistants and a warder, he stopped to converse with a male patient who 

 was only insane on one point and whose conversation was very interesting, j 

 Suddenly the man sprang up and struck a violent blow at the doctor's neck with 

 a large sharpened nail, and almost completely severed the carotid artery. The \ 

 warder seized the man, the assistant gave the alarm, while my friend sat down j . . 

 and pressed his finger on the proper spot to stop the violent flow of blood, which 

 would otherwise have quickly produced coma and death. Other doctors soon i •<'. 

 applied proper pressure, and a competent surgeon was sent for, who, however, ! :• 

 did not arrive for more than an hour. The artery was then tied up and the 

 patient got to bed. He told me of this himself about two years afterwards, and, 

 on my inquiry how the functions of the great artery had been renewed, he; 

 assured me that nothing but its permanent stoppage was possible, that numerous, 

 small anastomosing branches enlarged under the pressure and after a few months 

 carried the whole current of blood that had before been carried by the great! 

 artery, without any pain, and that at the time of speaking he was quite as wellj 

 as before the accident. Such a fact as this really answers almost the whole of 

 Herbert Spencer's argument which I have quoted at p. 256. 



