On my return to Churra, a change was observed in the character of the vegetation, all the Tradescantias had ceased, as well as most of the Impatientes, and Eriocaulons. The grasses had become more withered, and the general tint was brown. No kites (Falco milvus) are to be observed out of Churra.
The plants which were particularly conspicuous about Churra, were past flowering in the interior; thus Osbeckia Nepalensis? was not to be met with in flower in the interior, while it is in profusion about the station. The same may be said of other instances.
After all Churra presents the richest flora of any other place in the Khasyah hills, because there is a greater extent of wood near it, than is found in any other locality, much greater altitudes and deeper descents in its ravines, and it is as it were the transit point between a tropical or sub-tropical, and a temperate vegetation. I have no doubt, that within a circle of three miles of Churra, 3,000 species might be found in one year.
The principal plants pointing out the tropical nature of the vegetation are Pandanus, which is almost limited to the limestone formation, on which it is excessively abundant, Chamærops Martiana? which from its affecting particularly the walls of the amphitheatres so conspicuous about Moosmai, Mamloo and Surureem, and the depths of whose sides is probably at Mamloo 1,000 feet, might have been better named. I have never seen it on any other places. The Alsophila Brunoniana is likewise apparently confined to the limestone hills, while the tree fern, Polypodium, is found on sandstone, as well as Impatiens, Tradescantia, Commelineæ, Eriocauloneæ, Xyres, almost all the grasses, Melastomaceæ, almost all the Leguminosæ and the preponderance of tropical Rubiaceæ, which are, however, few, Scitamineæ, Epiphytical Orchideæ, Urena Labiata, etc. etc.
On the 23rd I went to Mamloo, which is about four miles to the west of Churra. To this place the limestone ridge, extending from Churra, nearly approaches: its vegetation is not rich but always stunted: rocky amphitheatres are very remarkable at Mamloo, they are of excessive depth; their walls being generally perpendicular, often somewhat overhanging. The manner of their formation is now to be seen in the amphitheatre immediately contiguous to the village, although it appears to be very slow. It is thus, bodies of water falling from the edge of the table land, seem to undermine the sandstone below, producing land slips, which occur in this manner year after year. Since 1835, the edge of the Moosmai fall has receded at least 10 feet, and ample evidence remains of the recession to take place next rains. This simple undermining will suffice for the formation of ravines, which are formed by their sides merely slipping down without being carried away, this last only occurring in the immediate vicinity of the strength of the torrent. All the different stages may be easily seen. The edge of the table land I take to have been originally at Mahadeb. The time that has elapsed between the falling of the first cataract over its edge, and the formation of the edge over which the waters at present fall, must be immense, since that edge has now receded several miles. Allowing the annual recess to be 5 feet, and the distance 5 miles; the time occupied would be 5,700 years: that the time has been great, is proved by the sides of these places being clothed with large tree-jungle to the base of the scarp.
October 25th.—I went in search of the fossil marine beach, (found during our first visit in 1835,) but passed it, and my journey ended at the site of the Jasper beds: this occupies a ridge where roads strike off leading to the Orange villages, so called from the groves of orange trees by which they are surrounded, and from which they derive their name. From this spot, 3 villages are seen occupying sheltered situations, none much above 2,000 feet in elevation. Luckily I was accompanied, (although going down I was unconscious of it,) by a boy who had been with McClelland when he originally discovered the fossil remains, so I recommenced the ascent, after digging in many places without any success. The site is scarcely 1,000 feet below Mamloo, which is 3,153 feet; it is below the ridge along which the road is visible from the village, and is about 100 yards farther from it than the second square stone erection. One would imagine that one was passing through rocks presenting nothing interesting: the rocks are in many places very hard, particularly when they have been long exposed to the atmosphere, in which case they are less red than when sheltered by vegetation, when they are soft and of a reddish colour: the fossils are by no means frequent, the cylindric tubes appear to occupy the outer or rather upper surface of the sandstone, in the interior of which Medusæ or Cyrtomæ are most frequent, accompanied by shells, some of large size, the largest bivalves resembling scolloped oysters; the next in size looking like oblong cockles: for only in one position did I see a conglomeration of minute shells; this occurred above the others and nearer the jungle. I brought away with me, two boxes full. Owing to my presuming that I should meet with water near, I omitted the precaution of taking some with me, so I could not ascertain exactly the height of the place. All the fossils are easily friable. [{172}]
From the Jasper, which is scarce 1,800 feet in elevation, the following plants occurred nearly in succession—Holmskioldia, this is scarcely found above 2,000 feet; Porana in abundance, gradually diminishing above; Callicarpa arborea abundant, continuing to about 2,200; Triumfetta, Urena lobata, Arundo the same as above, Melica latifolia, Panicum plicatum, and one or two other species; a Polygonum, Andropogon, small Commeline, Leea, Erythrina are very close to the spot, and the only Churra plant, except the Arundo and Wendlandia is a Labiata, Geniosporum? so is Composita arborea; indeed the vegetation is almost decidedly tropical. The following plants are then seen—Tetranthera, Flemingia as at Mahadeb, Vitis, Drymaria, Panicum eleusinoides, Eurya, Panax foliis decompositis inermis, Pogonatherum crenitum, Wallichia, which occur before one has gained an ascent of 2,000 feet: Osbeckia nepalensis descends to this but in small quantities; then I remarked Bidens, Ætheilema, Caricineæ, Rottlera, Didymocarpus, Begonia, Cheilanthes dealbata, Stemodia ruderalis? Scutellaria, Impatiens bracteata, Rungiæ sp. Sida, Elephantopus sp. and Bambusa, Gordonii occurring there at an elevation of about 2,100 feet. Then Centotheca lappacea, Deeringia, Panicum centrum, Gouania, Caryophyllus, which last occurs on all the chain of Himalayas, and which I have seen as high as 6,000 feet in the Mishmee Mountains, latitude 28°. Panax foliis palmatim partitis, Clerodendrum nutans, Ficus feruginea and F. hispida, foliis cordatis, serrato-dentatis: then Saurauja micrantha; before 2,300 feet were reached. There Oxyspora sp. paniculis cernius ramis ascendentibus, frutex, Croton of old, Ruellia persicæfolia appeared, and about 2,400 feet, the 1st Quercus appeared. Here, as at Mahadeb, Ruellia Neesiana became common, and Linum trigynum, Uncinia, etc. Grasses commence to preponderate at about 2,800 feet, but not the grasses of Churra. Holcus, Airoides, etc. not being found, but Panica varia, and Rottboellia which ceases above this.
At the raised Marine Fossil Beach, a queer Cephalanthus? Legumenosa arbuscula fol. pinnatis impari (Pongamiæ) Legumenibus secus suturam quamque alatis, Mangifera indici, Anthistiria arundinacea are found, and an arbusculous Mimosa, but unarmed. Shortly above this, Holcus, Andropogons, etc., begin to preponderate, and thence the vegetation is nearly that of Churra. The woods of Mamloo consist of Bucklandia, oaks, chesnuts, Panax, Hyalostemma, Eurya, and Oleineœ; Epiphytes are very common. The most remarkable tree is one foliis alternis bistipulat; corymbis denis, Calycibus hinc fissis, petalis 5-albis, Antheræ sinuosæ columna terminans, et ovarium et stigma occultantes? fructibus pendulis stipilatis ovato oblongis, carpellis 5-latere marginatus.
This has some affinities apparently with Sterculiaceæ; the flowers are perhaps polygamous.
Here Cypripedium insigne, Venustum, and various other fine Orchideæ may be found.