230 THE MENDEL JOURNAL 



limitations of daily time. Ars longa, vita brevis is true in this 

 respect, as in others. Many men accompUsh very little of a 

 definite nature in life, not because they are incapable or unworthy, 

 but because they attempt the impossible and endeavour to 

 express in deeds their all too varied interests. Such men are 

 not uncommon in the scientific world. It was once said of 

 Lord Brougham " that he would have been an excellent la\vyer 

 had he known a little law." There are, unfortunately, men in 

 every calling of life, who like Brougham have such a 

 varied interest in things that it may be said of them, " they 

 would be better workmen at their calling if they but knew a 

 little more of their work.'" Men of science, as well as those of 

 art, have to remember this, in order that something definite 

 and tangible may constitute the edifice which their Ufe leaves 

 behind it. 



In Section IV. Professor Poulton gives an account of Darwin's 

 connection with the University of Cambridge, one of whose 

 great and illustrious sons he was. It would be impossible here 

 to give a proper idea of the fascinating interest of this chapter. 



Sections V. and VI. deal respectively with the " Value of 

 Colour in the Struggle for Life " and of " Mimicry in the Butter- 

 flies of North America." Both these sections are largely written 

 from the historical standpoint, in order to restate, presumably 

 in Ught of present-day controversies, the bearing which the 

 facts of colour and mimicry have upon the conception of evolution 

 by means of continuous variations and of the origin of adaptations 

 through Natural Selection. 



Section VII. cannot fail to be of the greatest interest, since 

 here, we understand, a series of characteristic letters which 

 Darwin sent to Mr. Roland Trimen are published for the first 

 time. As we read Mr. Trimen's account of his first acquaintance 

 with Darwin, there are revived again the memories of the old 

 prejudices which the appearance of the Origin of Species 

 aroused in 1859. And, as for the letters themselves, '"' we feel, 

 again and again, as we read them, the presence of the bright, 

 courageous spirit that could pierce the dark shadow of lifelong 

 pain and discomfort, and preserve undimmed its humour and 

 its breadth of view." 



The Appendices A, B, C, and D are a little polemical in 

 nature. Appendix A revives the old controversy as to the 

 existence of single or multiple origins of species. Appendix B 

 considers Darmn's attitude towards the question of evolution 

 by mutation. Professor Poulton points out that Darwin's 

 critics and others from time to time called his attention to the 

 possibility of evolution through the agency of " monstrosities " 

 or " sports," and that Darwin very carefully at different periods 



