v.] PROPER STUDY OF DOMESTIC VARIETIES. 149 



perhaps all, variation is the result of the conditions or 

 circumstances in which the organism is placed. Van 

 Mons plainly propounds that the causes of variation are 

 change of soil, of climate, or of temperature ; but he 

 assumed, in common with most thinkers of his time, 

 that species are essentially distinct and immutable. 

 Therefore, he could not look upon variation as anything 

 more than an incidental feature in nature, and whatever 

 the causes of this variation may be, they are significant 

 only as they explain how the cultivator may manipulate 

 his plants, not as throwing any light upon the evolution 

 of the vegetable forms which cover the earth. It is rea- 

 sonable to suppose that the origination of new kinds of 

 plants in the garden is but a local or specialized ex- 

 pression of the means of origination of all forms of 

 plants, whether in the garden, field, swamps or woods. 

 I am constantly reminded that horticulturists do not 

 apprehend the fundamental principles of the origination 

 of new varieties simply because they refuse to look at 

 the problem broadly, in the light of evolution, and per- 

 sist in asking for some short-cut or so-called practical 

 method which they can apply in the garden without test- 

 ing its probable fitness by comparing it with the means 

 which are operative in the uplifting of the vegetable 

 world. Horticulture has always suffered by being cut 

 off from the studies of scientific men, so that it has grown 

 too much into a mere art, which is not conceived to 

 rest upon the very same fundamental laws, so far as 

 plant -breeding is concerned, as have been and are the 

 slow but mighty forces which have been operating 

 throughout the ages. 



You are now wanting to ask how it was that Van 

 Mons obtained such useful results if his system were 



