10 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



the direction of augmented size, but not, so far as the writer has 

 observed, in better colour. 



The next alliance, clustered around A. multiflorus, our most 

 widely diffused species, contains only one which has been much 

 known in gardens, namely, A. amethystinus, which has been 

 called A. pilosus and bostoniensis. 



In the group of Divergentes there are three species which 

 vary in many ways, namely, dumosus, vimincus, and diffusus. 

 One of the varieties of the latter is a favourite in cultivation. 



The group Vulgares, a large alliance, takes all the rest of the 

 members of the section. The first species in Dr. Gray's list has 

 been " cultivated from earliest days in European gardens," and 

 in some places on the Continent it has shown a tendency to 

 escape and establish itself in open places and by roadsides. 

 The larger and beautiful A . Novi-Bclgii has been cultivated both 

 in the old world and in the new, and some of its varieties are 

 favourites. Many other species closely allied to this are found 

 in the West, three Atlantic species representing the alliance in 

 the East. The latter are A. tardiflorus, prenanthoides, and 

 jncniceus, with its varieties. A. puniccm is conspicuous for its 

 wide range of colour. 



We pass next to the subgenus Erigerastrum, having two 

 Alaskan species which need not for our purpose be further men- 

 tioned, and to the two subgenera Doellingeria and Ianthe, among 

 which are placed the species formerly assigned by Torrey and 

 Gray to Dipplopappus. Some of these are pretty, but are hardly 

 of horticultural interest. The subgenus Orthomeris has a simple 

 pappus, and comprises some of our most widely spread species. 

 Many of them are mountain and swamp plants, presenting 

 peculiar difficulties in cultivation. 



Of the remaining subgenera, Oxytripolium, Conyzopsis, and 

 Macha?ranthera, we are inclined to single out only A. Bigclovii 

 for special mention. This is a beautiful plant, having a wide 

 range of variation and susceptible of immediate improvement in 

 a rich garden. 



Incidentally, attention has been called to the distribution of 

 some of the species in these different subgenera ; allusion must 

 now be made to some practical considerations based thereon. 



The habitat of a plant is by no means a sure guide as to the 

 soil, exposure, and treatment which it should receive in a garden. 



