78 DISEASE IN PLANTS. 



important process of rigid selection i.e. by 

 choosing the best of the progeny and breeding 

 from them apart from the parent-forms, and 

 gradually intensifying, as it were, the variations 

 in certain directions which have been started by 

 the crossing. 



It is by selection, careful culture, and repeated 

 selection that so much has been done in obtaining 

 the innumerable new varieties of roses, sweet-peas, 

 orchids, orchard fruits, cereals, grapes, strawberries, 

 melons, tomatoes, early potatoes, etc., brought 

 forward by numerous breeders of plants in all 

 countries, as will readily be understood if reference 

 be made to the work of Hays and Webber in 

 America ; Saunders in Canada ; Garton, Sutton, 

 Veitch, Bateson, and others in this country. 



Nor is it necessary that the new materials 

 for selection to work upon should be started by 

 hybridisation. Grafting, change of conditions, and 

 even variations so vaguely understood that we 

 term them " spontaneous," may supply the starting- 

 points for changes in the characters of plants, so 

 remarkable after intensification by breeding that 

 people find it difficult to believe they can have 

 come from one stock. 



Here, however, I must conclude, merely re- 

 marking that the above sketch is a mere outline 

 of the subjects modern agriculture and horticulture 

 concern themselves with. There are hundreds of 

 problems connected with the germination of seeds, 

 on which valuable recent work has been done by 

 Klebs, Green, Horace Brown, and others ; with 



