362 



Beport on the Tea Plant of Upper Assam. 



{Oct 



that under the same ch-cumstances the narrower the valley the greater 

 will be the number of northern or elevational forms discovered daring a 

 progress through it, although the reverse will obviously be the case if a 

 wide and a narrow valley be submitted to complete investigation, be- 

 cause in the former ease the boundary hills being distant, a variation in 

 their floras may be expected. 



I have offered these remarks, not because they bear much on the 

 question as it now stands, but because they will do so if a more exten- 

 sive comparison be ever made upon good data between the floras of 

 Upper Assam and of the Tea districts of China. 



I have already adverted to the low temperature, during the hot 

 months, of the two great rivers the Dihong and Brahmapoutra proper ; 

 the influence they exert, is well shewn by the fact, that some of the 

 most valuable forms are confined to their immediate banks. It must be 

 confessed, however, that further inquiries are requisite on this head, 

 I cannot conclude this portion of my report in a better mode than by 

 observing, what is certainly suflaciently remarkable, that of the eight 

 genera, adduced by Mr. Royle as proving the similarity of the flora 

 of the mid region of the Himalayas with that of the mountains of the 

 central provinces of China, five are found in the plains of Assam, viz, 

 Eurya, Stauntonia, Kadsura, or Sphoerostemma, Hovenia, and Ophio- 

 pogon. 



Mr. Griffith proceeds to a comparison between the climate of Upper 

 Assam and that of the province of Central China ; and an examination 

 into the nature of the stations of the Tea plant in the provinces of Kiang- 

 nan and Kiang-see, Passing over these, we will introduce his 



Remarks on the genus to which the Tea Plant belongs, with remarks ori the 

 geographical distribution of the Indian Plants of the natural order 

 TernstrcB miacea. 



Most botanists appear to have agreed, but on what grounds I know 

 not, that the plant furnishing Tea is generally distinct from Camellia. 

 Without entering minutely into the histoiy of these genera, it will be 

 sufficient for me to state that Linnaeus, Decandolle, Hookefx, and Cam- 

 BESSEDES appear to have no doubt on the above point; and the last^author, 

 who has written a monograph of the order Ternstrosmiacese, places the 

 two genera at considerable distances from each other. This unnatural 

 separation appears, however, to have partly arisen from the author not 



