PARTICULAR EVIDENCE FOR 207 



The drawback to abstract biology based on first principles 

 is that it enables its devotees to develop arguments which 

 seem plausible until they are reduced to the concrete. 



§ 9. 'Particular Evidences in support of the Affirmative Answer 



The question is whether modification-inheritance does or does 

 not occur, and we must no longer postpone our consideration 

 of the concrete evidence used to support the affirmative position. 

 Our reason for not placing this section in the foreground of the 

 chapter is mainly that a multitude of misunderstandings have 

 had to be cleared away before the so-called direct evidence 

 could be profitably considered. When one naturalist, Dr. W. 

 Haacke, declares that instances of modification-inheritance are 

 as plentiful as sand on the shore, and another, Prof. E. Ray 

 Lankester, declares that the Lamarckian position has its only 

 remaining defence, and that no secure one, in Brown-Sequard's 

 experiments, we have obvious justification for our preliminary 

 discussion. 



The instances adduced as evidence of modification-inheritance 

 might be classified according to the errors involved, but we have 

 arranged them rather in reference to the general nature of the 

 modifications discussed, whether environmental or functional, 

 whether tending to increase or decrease, and so on. The alleged 

 inheritance of the direct effects of mutilations, injuries, and the 

 like is discussed separately in §§ 10 and 11. 



ImproYement in Trotting Horses. — Over a hundred years ago 

 (1796) the utmost speed of the English trotter was stated at a 

 mile in 2 min. 37 sec. Since 1818, accurate records have 

 been kept, which show a gradual increase decade after decade 

 in the speed and in the percentage of swift trotters. The 

 standard has risen and the breed has improved. The mile can 

 now be run in 2 min. 10 sec, or less. It is claimed by Cope 

 and others that we have here direct evidence of the trans- 

 mission of the structural results of exercise. 



