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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Sir Joseph then proceeds to describe forty-six species, of 

 which the last three were then imperfectly known, as belonging 

 to British India, and I believe others have since been discovered. 



The same high authority, in the Botanical Magazine for 

 1890, table 7149, writes : " Judging by the results of botanical 

 explorations lately made in Western China, it would appear that 

 all previous estimates of the number of species of this magnifi- 

 cent genus of plants are far below the mark, and that the 

 discoveries made in the Eastern Himalaya are only harbingers 

 of what are to be expected from the vast mountain regions still 

 further to the east. It is interesting to trace the development 

 of the genus across the Old World, and it may be thus sum- 

 marised. In Europe three occur in the extreme west — 

 lapponicum in Norway, ponticum in South Spain, and fcrru- 

 (jineum in the Pyrenees ; the latter occurs in the Alps of Middle 

 Europe with hirsutwn, but does not extend into Asia, where 

 ponticum reappears in Asia Minor, Syria, and in the Southern 

 Caucasus with flavnm and caucasicwn. The latter country 

 (the Caucasus) is the eastern limit of these three. Excluding the 

 few high Northern Asiatic species, none are found east of the 

 Caucasus till entering the Afghan region, to which a/ghanicum 

 and Collet tianum are confined. On reaching the Himalayan 

 region the development of the genus advances with rapid strides. 

 Four species are found in the Western Himalaya between 

 Cashmir and Nepal, arboreum, campanulatum, barbatum, and 

 anthopogon, all of which advance to Sikkim, where twenty-nine 

 have been collected. East of this province again, Bhotan has- 

 only twenty-five, seventeen of which are Sikkim species, but 

 considering how imperfectly that great and lofty province has. 

 been explored (its alpine regions not at all), it may safely be 

 assumed that this number does not include half of what it 

 contains. Proceeding eastwards little is known of the vegetation 

 till China is entered, and as Mr. Hemsley informs me that 

 between sixty and seventy species have been collected in its 

 barely entered western mountains by Pere David, Dr. Henry, 

 and others, it may be regarded as probable that the Celestial 

 Empire contains more species of this genus than all the world 

 besides." 



1 may here add that in the current June number of the 

 Bot inical Magazine, table 7801, is figured Rhododendron race- 



