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JOURNAL OF. THE ROYAL HORTICULTURAL SOCIETY. 



these beautiful flowers within the space of a few yards, and 

 under exactly similar conditions. 



With regard to the flowering period of these perennial Sun- 

 flowers, I think we might conveniently divide them into three 

 seasons — late summer or early autumn, mid-autumn, and late- 

 autumn. To the first group belong the early form of rigidus 

 (which I have named cestivus), and mollis, which is a very distinct 

 and rare species. To the second group belong the other rigidus 

 forms, divaricatus, multiflorus and its varieties, occidentalism 

 Maximiliani, decapetalus, giganteus, and Icuvigatus, while to the 

 last group belong Icetiflorus, angustifolius, orgyalis, doronicoides, 

 grosse-serratus, and tuber osus, which in its cultivated form rarely 

 flowers in this country. The first section begins flowering 

 towards the end of July or early August, followed by the other 

 rigidus forms, which carry on the mid-season until we have them 

 at their best in September. These are followed by the late 

 group, which flower until cut off by the frost. 



With few exceptions these perennial Sunflowers are distinct 

 enough in habit and flower- colouring to be included in their 

 entirety in at least every large garden. Where space is limited, 

 however, the grower will make a choice suitable to his own par- 

 ticular requirements. 



Dr. Gray, as might have been expected with so many years' 

 constant study, did his work carefully and well ; but, with the 

 greater light thrown on H. rigidus in recent years, I hope we 

 may be pardoned for introducing a modification that may some- 

 what simplify matters. What we want particularly to do is to 

 draw a line between H. rigidus and H. Icetiflorus that will be 

 more readily grasped than that given by Dr. Gray, and which 

 depended chiefly on the yellow or purple discs. This character 

 we find most unreliable, as even among the early-flowering 

 H. rigidus we have distinctly yellow as well as purplish discs. 

 I have also attempted a key by which we may at least place 

 those in cultivation in three groups; In the first, the involucral 

 bracts are short, ovate, obtuse, or acutish — example, H. rigidus ; 

 in the second, the involucral bracts are half as long again as the 

 last, ovate, lanceolate-acuminate, or attenuate-acute, including 

 Icetiflorus as we have defined it, occidentalism mollis, lecvicjatus, 

 and doronicoides ; and, lastly, group three, in which the invo- 

 lucral bracts are nearly as long again as the last, loose, somewhat 



