282 THE BOTANY OF THE KACHIN HILLS NORTH-EAST OF MYlTKYiNA. 
626. Helminthostachys zeylanica Linn^ 
Myitkyina (C). DiSTRlB. South-Eastern Asia and Australia. 
627. Ophioglossum vuigatum Linn. 
Myitkyina (C), Distrib. Cosmopolitan. 
§ 4 .— Nature and Relationships of the Kachin Flora. 
{D. Prain.'] 
Though the collection dealt with in this paper is no doubt only 
a partial one, a perusal of the list of species will show that it possesses 
considerable interest. This interest depends to some extent on the 
fact that no previous collection has been made in this particular 
district; it is, however, intensified by the geographical position of the 
region whence the species are derived. The Kachin Hills constitute, 
roughly speaking, the upper catchment-area of the river Irrawaday, 
Which was formerly supposed to derive at least some part of its waters 
from the Tibetan table-land but which we now know to have no trans- 
Himalayan tributaries. Though the botany of the Kachin Hills 
proper has remained till now quite iminvestigated, collections have 
been made in the Hukung Valley immediately to the west and in the 
Taping Valley immediately to the south-east ; the former by Dr. 
Griffith, the latter by Dr. J. Anderson. The Hukung Valley plants of 
Griffith have beeiT, in the majority of instances, dealt with in the 
Flora of British India) those from the Taping Valley, owing to 
their place of origin being, politically, part of China, are eni?merated 
in the Index Sinensis of Forbes and Hemsley. These Taping 
Valley plants, as an examination of our Kachin list will show, are, 
Bowever, only accidentally Chinese. Of the 627 plants enumerated, 
173, or about -/gths (more accurately 27*59 per cent.) of the whole, 
occur in the Taping Valley, though less than half of these (only 78) 
have been found in China outside the limits of this particular valley. 
Ncr is this all; two-thirds of the plants that do occur in China out- 
side this valley are in no sense characteristic of any particular portion 
of South-Eastern Asia, since they occur in Indo-China, Malaya, the 
Himalayas, Assam and India, as well as in China. As a matter of 
fact, onlyffive of the plants that are common to the Kachin Hills and 
the Taping Valley extend eastward to China without occurring 
in Eastern Indo-Cliina as well, and two of these four are not dis- 
tinctively Chinese plants, since they occur in Assam as well as in 
China 1 one of the two appearing in the Eastern Himalaya as well. 
Nor has the I'aping Valley any more marked affinity with the 
