CHAP. VI. HYBRID PLANTS. 289 



Europe; and altogether about forty cases of wild reputed 

 species have been collected by Schiede, Lasch, and De Can- 

 dolle. It is difficult not to believe that a great number of 

 the reputed species of Salix, Rosa, Rubus, and other intricate 

 genera, have also had a hybrid origin. 



This, as De Candolle justly observes, is an answer to those 

 who, like Linnaeus, have assumed that the number of species 

 of organised beings has been constantly augmenting, since the 

 creation, by the intermixture of diiferent races. All the ob- 

 servations that have been made for the last century have not 

 produced a catalogue of 50 certain hybrids in a wild state. 



In a practical point of view, I am inclined to believe that 

 the power of obtaining mule varieties by art is one of the most 

 important means that man possesses of modifying the works of 

 nature, and of rendering them better adapted to his purposes. 

 In our gardens some of the most beautiful flowers have such 

 an origin ; as, for instance, the roses obtained between 

 R. indica and moschata, the diiferent mule Potentillae and 

 Cacti, the splendid Azaleas raised between A. pontica and 

 A. nudiflora coccinea, and the magnificent American-Indian 

 Rhododendrons. Bj^ crossing varieties of the same species, the 

 races of fruits and of culinary vegetables have been brought 

 to a state as nearlj' approaching perfection as we can sup- 

 pose possible. And if similar improvements have not taken 

 place in a more miportant department, — namely, the trees that 

 afford us timber, — experience fully warrants the belief that, 

 if proper means were adopted, improved varieties of as much 

 consequence might be introduced into our forests, as have 

 already been created for our gardens. 



It is, however, to be regretted that those who occupy them- 

 selves with experiments of this kind do not confine them to 

 woody or perennial plants which can be perpetuated by cut- 

 tings. Mule annuals have the great fault of perishing almost 

 as soon as they are obtained, and they serve no other purpose 

 than that of encumbering the records of science with accounts 

 of plants which, from their transitory existence, can never be 

 re-examined. 



In conducting experiments of this kind, it is well to know 

 that, in general, the characters of the male parent predomi- 



u 



