540 SCIENCE PROGRESS 



experiment made by Mr. A. P. di Cesnola, who having exposed 

 some dozens of the two forms of Italian Mantis, green and 

 brown in colour, some in herbage which matched their colouring 

 and others in herbage which did not, found that the latter were 

 soon taken by birds whilst the former were left. Thus the 

 survival value of the protective colouring was distinctly proved 

 but not its cumulable inheritance from generation to genera- 

 tion nor the variability of the species nor the survival value 

 of small differences, of all of which we have ample proof in the 

 phenomena of domestication. As to the point that is proved, 

 far be it from me to detract from the cogency of the proof but 

 why is it more conclusive than any one of an infinite number 

 of experiments tried by humanity during hundreds, if not 

 thousands, of years by which they have unintentionally 

 demonstrated the survival value of this very character of colour 

 in other ways ? Colours have been points selected by breeders 

 and gardeners in the case of cattle, dogs, pigeons and numerous 

 flowers during centuries. In the one experiment, a few dozen 

 Mantis were demonstrated to have survived by virtue of colours 

 corresponding with their surroundings ; in the others, millions 

 of plants and animals have survived and have been selected as 

 progenitors of the future race by virtue of colours corresponding 

 with preconceived ideals of beauty in the minds of men. Nature 

 in both cases is the selector; in the one case her selective agents 

 were birds, in the other case men. In either case has the 

 possession of a particular colour been a favourable variation 

 determining the survival of a particular animal or plant in 

 competition with his fellows less fortunately endowed. Why 

 is the single experiment more cogent than the million ? 



Again Dr. G. Archdall Reid is one of the ablest of present- 

 day exponents of organic evolution especially in relation to man 

 and his treatment of the subject of elimination by disease ought 

 to have and doubtless has gone far to dissipate the dense fog of 

 much loose writing on the supposed immunity of modern man 

 from Natural Selection. Yet he writes (Bedrock, No. 2, p. 262) : 

 " It is necessary ... to ascertain whether Natural Selection 

 does really occur in Nature, to observe what kinds of variation 

 it selects and to discover the result, if any, of this selection. It 

 is useless to observe domesticated plants and animals ; they are 

 under artificial selection." But why does the fact that they are 

 under artificial selection make it useless to observe domesticated 



