THE JOURNAL 01 THE LINNEAN SOCIETY, On a Collection of Plants from Upper Burma and the Shan States. By Brigadier-General H. COLLETT,C.B., F.L.S., and W. BOTTINGHEMSLEY, F.R.S., A.L.S. [Read 7th November, 1889.1 (PLATESI.-XXII., and Map.) INTROUUCTIOK. (By General Collett.) I PROPOSE to communicate to the Linnean Society some par- ticulars of a collection of plants made in 1887 and 1888 in the neighbourhood of Meiktila, in the plains of Upper Burma, and in the Southern Shan States, on the eastern frontier of that pro- vince. I began collecting plants in this region partly to gratify my own love for botany, and partly in response to the request of nly friend Dr. G. King, F.R.S. From time to time, as the plants were collected, they were transmitted to Calcutta and incorporated in the general herba- rium there ; for I had then no idea of publishing any account of them. Dr. King and his assistant, Dr. D. Prain, compared and approximately named the species that I had failed to identify, and they were.many, and furnished me with the names, from which it appeared that I had collected a number of novelties. I also learned that nothing had been published on the botany of the Shan hills. Undec these circumstance;, aud encouraged by LI”. J0URN.-BOTANY, VOL. XXVIII. B 2 UENERAJ. COLLETT AND MR. W. B. HEMSLEY ON PLLXTS Dr. King, I decided that the collections should be worked out critically. This has been done at Kew by my friend Mr. Hemsley ; and I am told, by those better able to give an opinion on this subject than I am, that the results and particulars are of sufficient scientific interest for publication. I therefore submit this paper to the Society in the hope that I may thus, in some humble measure, advance the science of systematic and geogra- phical botany. As I have already mentioned, my original object wm not publication, consequently I did not observe and note with that exactitude I should otherwise have done, and I have to solicit the indulgence of the Society for any shortcomings due to this cause. As soon us it was decided to publish an account of the col- lection, Dr. King and his assistant, Dr. Prain, cheerfully under- took the laborious task of going through the Calcutta Herbarium to take out the specimens previous to seuding them to Kew. The critical comparison they have been subjected to there has revealed the existence of a much larger number of new forms than was anticipated, and a few of the most remarkable are here exhibited for the iuvpection of the Fellows. The collection is, of course, very far indeed from a complete representation of the flora of those little-known regions, but it may serve as a fair sample of the composition of the vegetation. - Excluding a few probably introduced plants, and the Grasses, which wye sent to Mr. Duthie, F.L.S., Superintendent of the Saharuupore Botanic Garden (who is making a special study of this natural order), and have not reached England at the time of writing, the total number of species of Phauerogams enume- rated is about 725, belonging to 460 genera and 109 natural orders *. But before proceeding to Mr. Hemsleg’s analysis of the relationships and geographical distribution of the elements of this sample of the flora, I will give Home of the more salient * The enumeration, it should bj stated, also includes some plants collected for me by Surgeon N. Mandors, of the Medical Staff, while he was attached to the Southern Shan Column during the cold season of 1887-88, and while qiistered at Koni in the Shan hills during the summer of 1888. Mr. Manders collected several interesting novelties, and his name is appended to all the plants he collected. We have likewise added, with the assent of the collector, a few plants collected by Mr. Aplin, of the Indian Forest Department, and reported on by him to the Chief Commissioner of Burma. XROX nPPER BURMA AND THE SHAN STATES. 3 €iatures of the physical characters of the country and the aspects of the vegetation. Concerning the plants from the plains of Upper Burma little need be said. Grif6th and Wallich collected in the neighbour- hood of Ava fifty years ago, and there are not many novelties from this region-the plants being chiefly of the same species discovered by those botanists, yet often valuable, because afford- ing better material of obscure species founded upon imperfect specimens. The general character of the flora of Lower Burma is suf- ficiently well known from the researches of Eurz, Parish, and other botanists, but it differs widely from that of Upper Burma, due to the very different climatal conditions prevailing in the two regions. In Lower Burma the annual rainfall is seldom much short of 100 inches, and it nourishes a purely tropical vegetation ; whereae in the wide and arid plains which form the greater p&’bf Upper Burma the rainfall diminishes to a yearly average of abollt 80 inches, and the general aspect of the vegetation B striking resemblance to that of the dry plains of the Deccan in Southern India. The Hhaa Hills and Plateaux. We have here to deal with a more interesting and novel area, which had never before been botanically explored, and which has yielded, even in the partial collections now under review, a re- markably large number of new and interesting plants, amounting indeed to about 12.5 per cent. The petty provinces comprising tlie territory known as the 8han States, or Shan Hills, extend along the entire eastern frontier of our Burmau possessions, from the Chinese province of Punnan on the north and north-east to Siilm in the south; and consist, speaking broadly, of several distinct ranges of hills, rising in occasional peaks to a height of 6000 or 7000 feet, and running north and south, enclosing elevated plateaux of from 3000 to 4000 feet above the sea-level. The Shan States are divided for administrative purposes into Northern and Southern ; and it is the latter division with which we are immediately con- oerned, as it is almost exclusively iu this area that the present collection of plauts was made. The States may be roughly defiued as comprised between the B2 4! GENERAL COLLETT AND MB. W. 5. HE'dSLXY ON PLANTS 19th and 22nd parallels of North latitude, and as bounded on the east by the Salween river, and on the west by the plain of Upper Burma. Along the whole western border of this mountainous region runs the belt of jungle locally known as '' the terai," which inter- poses its malarious valleys between the plain country and the healthy plateaux of the interior hills. This fringe of forest, or terai, presents the usual features characteristic of similar belts of jungle bordering the foot of the Himalayas, from north-east to south-west. Up to about 2000 or 2500 feet of elevation the forest is dry, the soil poor, and the trees more or less stunted in their growth, forest-fires being of frequent occurrence. Under- growth is almost absent, and bamboos and Dipterocarps, asso- ciated with species of Stereospermam and Dillenia and a few climbers, such as Spatholobus and Congea tomentosa, are the most prominent features of the vegetation. On attaining a higher elevation, from about 2500 to 4000 feet, the character of the vegetation is much changed, owing in part to the greater humidity, in part to a lower temperature. The trees are much larger ; mosses, lichens, and ferns abound j the hill-sides are covered with undergrowth, and numerous trees and herbaceous plants appear which are not represented at lower levels: such are Quercus, Schima WalEichii, and two or three arboreous Composite. This is the principal forest, from the gloomy depths of which the traveller passes, at about 3500 or 4000 feet of elevation, by one step, to the open breezy plateaux intervening between the forest edge and the next range of moun- tains. It causes a pleasant feeling, after marching for two or three days along narrow paths, cut through dense jungle, and breatbing a stagnant atmosphere, to mount the last ascent and emerge, quite unexpectedly, into the cheerful light of day, seeing before one rounded grassy hills, wibh occasional clumps of oak or pine, and crowned in the blue distance with the pic- turesque pagodas of some Shan village. It is the plants of these rolling plateaux, and of the precipitous limestone hills which rise above them, that have yielded the greater number of the novelties described in this paper. The general geological formation of the plateaux is a water- worn limestone, with occasional interposed sheets and boulders of conglomerate, underlying a sedimentary deposit of fiue- grained red clay or loam, varying in thickness from a thin super- FROM UPPER BURMA AND THE SHAN STXFES. 5 ficial covering up to three or four hundred feet, according to the amountof denudation it has undergone. This mantle of red clay at one time certainly overspread the whole country, probably 6 at. a nearly uniform level, for patches of it, like raised beaches, seen clinging to sheltered hollows in the black limestone ridges which rise through it in long pardel folds-remnants, no doubt, marking the ancient level of the red clay, as deposited in the quiet depths of an ocean or large lake. The underlying limestone, wherever exposed to view, is seen to hare been worn into rounded hollows and projecting bosses, apparently by the action Of water, at a time when it was exposed to d~udnt' 1011; and, like limestone in other parts of' the world, it is full of clefts, crevices, and caverm, communicating with each other to form, subterranean channels into which a great part of the superficial drainage of the country disappears.