80 DR. THOMSON'S MISSION TO THIBET. 
Cerastium, some Polygona, an Elsholtzia, Hypecóum, Convolvulus arven- 
sis, Lamium amplexicaule, Chenopodia, and Lycopsis abound; and along 
the edges of the fields may be seen a Mentha, Medicago, Melilotus, 
Nepeta, a spinous-calyxed Ballota, a ay Cynoglossum, Heracleum, 
Capsella Bursa-Pastoris, Sisymbrium ia, Lepidium ruderale, and a 
larger coarse species, a Thalictrum, a pein a Geranium, anda 
large coarse yellow-flowered Solanacea, probably a new genus. In the 
grassy meadows the commonest genera are Pedicularis, Gentiana, Poten- 
tilla, Astragalus, Ranunculus, several species of each, Plantago, Euphrasia 
(officinalis), Senecio, Allium, Galium, Taraxacum, Carum, Epilobium, Iris, 
and Gnaphalium. Among marsh-plants may be mentioned Triglochin, 
Hippuris, Veronica Anagallis, Ranunculus Cymbalaria; Glaux mari- 
tima, and a white-flowered Taraxacum which abound where the soil is 
saline. The open barren tracts, as I have already said, were rather 
productive in early spring, at which time numerous Crucifere, Borag- 
inee (mostly Echinosperma) and Astragali occurred. The brilliant 
rose-coloured flowers of Oxytropis chiliophylla often covered large tracts. 
Several species of Corydalis, a Euphorbia, a Matthiola, Nepeta. Jloccosa, 
Ephedra, Capparis, Echinops, Guldenstädtia, Tribulus, and several 
Artemisia, may also be mentioned. Shrubby vegetation is far from 
common, and only where there is a certain degree of moisture. Two 
Myricarie are common along the banks of streams, especially on gravel, 
and to them in Nubra is added a Tamarix. Hippophae occurs every- 
where near moisture, and Rosa Webbiana ventures even into the barren 
tracts. Į am not aware whether this Rose has been introduced into 
England ; but if not, it would (I think) be an acquisition, as it grows 
to a considerable height,—10 to 15 feet, forming large hemispherical 
tufts, completely covered with large red flowers. In one or two places I 
met with a yellow Rose, but exi in gardens, and always with double 
flowers. Several Willows, a Lycium, a Rhamnus, and at least three 
Lonicere, are the other shrubby site: the latter extend up the lateral 
valleys towards the alpine region, and in these, in addition to nume- 
rous Willows, a Poplar with cordate leaves (P. balsamifera?) occasion- 
ally occurs. The alpine shrubs are only Willows and Caragana versi- 
color. I think I mentioned to you last year that I found an unknown 
tree, with leaves very variable in shape, on the banks of the Shayuk. 
This year I have again met with it, but, as before, without flower or 
