where ground smooth by ice into great bosses and slopes, in the fissures of which nestle many curious little alpine plants.

I stayed here four days, taking walks in different directions, ascending some of the nearest mountains, exploring little hidden valleys, and everywhere finding flowers quite new to me, and of very great interest. The Pentstemons were of great beauty, especially one which grew in fissures of the granite rocks, with clusters of sky-blue flowers and yellow buds, forming a most striking combination. The curious and beautiful Pedicularis groenlandica was common in bogs, with tall spikes of purple-red flowers, having long, strangely-curved beaks, giving the appearance of some fantastic orchid. The genus Gilia was abundant in various curious modifications, one species (G. pungens) being like a minute furze-bush. On some of the hillsides there were sheets of the pretty butterfly-tulip (Calochortus Nuttallii), and in moister places the blue Camassia esculenta, the very dwarf Bryanthus Breweri like a miniature rhododendron, the pretty starlike Dodecatheons, the brilliant Castillejas, and a host of others. Eriogonums, allied to our polygonums, were abundant and varied, and there were many curious composites and elegant little ferns in the rockcrevices. One of the higher mountains was of volcanic rock, and having once seen their characteristic forms, it was evident that most of them were of this formation, being the sources of the great extent of Pliocene lava streams and ash-beds which cover so much of the country in California, Nevada, and Idaho. The older rock here is a kind of gneiss, full of fragments of other rocks, both crystalline and volcanic, producing a result similar to the rocks I found in the granitic region of the Upper Rio Negro, and which I have figured in my “ Amazon and Rio Negro" (p. 423, cheap ed. p. 293). The smooth, rounded forms of the rocks here are plainly due to glaciation, and have quite a different character to the globular or dome-form at the Yosemite and in Brazil, due to sub-aërial decomposition and exfoliation. Here they show the remains of what were rugged or jagged peaks worn down smooth into rounded hummocks of very varied forms. Striation is sometimes faintly visible,

but under the intense climatic changes of this region, weathering has in most cases quite obliterated it.

Having read Miss Bird's account of Lake Tahoe as being superbly beautiful, I determined to see it, and if the country looked promising to stay a few days. I accordingly left by the train on Monday morning, stayed the night at a very poor hotel at Truckee, and took the stage at seven the next morning for the lake, a distance of fourteen miles. The road was up a very picturesque, winding valley, very precipitous and rocky on the east side, more sloping on the west. The bottom of the valley seemed to be granite or gneiss, but the craggy heights on the east side were all of lava, sometimes scoriaceous, sometimes almost columnar basalt, and occasionally laminated. Sometimes there were precipices, peaks, and detached pillars of scoriaceous lava, two hundred to five hundred feet high, of strange forms and highly picturesque. This valley had a rapid stream, which was the outlet of the lake. It had once probably been full of lava and ashes, when the lake would have been much deeper and larger. This was indicated by stratified deposits in places at different levels, and by layers of rock full of rounded pebbles. The lake itself, though a fine piece of water, did not come up to my expectations. The mountains around were bare and monotonous, rather higher and snow-flecked on the west, but the highest peaks visible not more than ten thousand feet. On the west side there was most wood, but the mountains were not more than two thousand to four thousand feet above the lake, and therefore not high in proportion to its size, which is thirty-five miles long and fifteen miles wide. It is really less striking than Loch Lomond or Windermere, where the mountains are more picturesque and more precipitous; while it can bear no comparison with the sub-alpine Swiss and Italian lakes.

I strolled about the shores of the lake, and into some of the woods near, but all was very dusty and arid, and I found only a few flowers already familiar to me. The hotel looked clean and comfortable, and I had a very good dinner there, and in the afternoon sat on the verandah admiring the view over the lake, it being too hot and dry to go out. I was glad

I had seen it, and especially the valley up to it, but I had preferred to get on to the Rockies as soon as possible. I therefore went back to Truckee by the return of the stage in the afternoon, and went on to Reno by the evening train. While waiting at the station two ladies addressed me, and Isaid they had met me last autumn at the meeting of the American Association at Boston. They were both botanists, and had been camping out in the Californian mountains; so we compared notes, and had some interesting botanical conversation. Their names were Miss J. W. Williams and Miss Sarah W. Horton, of Oakland, California.

The line from Truckee to Verdi (twenty-four miles) passes through a very interesting series of gorges in the volcanic district. The rocks and precipices exhibit all the varied characteristics of basalt, lava, and volcanic ash, with frequent intercalated layers of gravel and glacial drifts. The lateral gorges give frequent peeps into the interior, with strange castellated cliffs and pinnacles. Sometimes the main gorge narrows, leaving barely room for the railway, with the river foaming against the black, rugged precipice. The whole country from Gold Run, in California, to Verdi, in Nevada (eighty miles), is a region of extinct (Pliocene?) volcanoes, but at and near the summit these rocks have been denuded down to the gneiss and granite, which there exhibits the grinding power of ice as in the mountains of Europe. In this region we have the results of fire, water, and ice action, well illustrating their respective shares in modelling the earth's surface. The long and deep valley of the Truckee has probably been entirely excavated through volcanic rocks since a quite recent geological period.

Leaving Reno the next morning, we passed through similar volcanic country for about fifty miles, in the Truckee valley; then across an arid pleateau to the valley of the Humboldt river, only reaching stratified rocks at the Humboldt mountains, towards the source of the river, in the evening; and the next morning found ourselves near Ogden, where I changed for the Denver and Rio Grande Railway, in order to see a different portion of the mountains, two hundred miles fur

ther south, and to visit Colorado Springs and the celebrated Garden of the Gods.

I left Ogden at 10 A. M. July 14, passing Salt Lake City, about fifty miles beyond which, near Provo, we entered a fine gorge of the Wasatch mountains, leading to an upland valley with abundant vegetation. The cliffs were of a red conglomerate with pebbles, and among the flowers I noticed Cleome integrifolia, yellow anotheras, handsome thistles, a fine golden-rod, and red Castillejas. When the train stopped at small stations, for water or other causes, I would jump out and gather any flowers I saw near me, keeping a sharp watch for the conductor's cry of "All aboard." Having with me Coulter's "Flora of the Rocky Mountains," I was able to make out many of the species. Climbing up a high, open valley, we reached Soldier Summit, where there was half a mile of snow sheds. This was the divide between the Salt Lake and the Colorado basins, and we then entered Pleasant Valley, and winding about came to the picturesque Castle Gate, where a mass of rock like the ruins of a mediæval castle rises close to the line. Passing this, we entered an almost desert region, with great bare flats of mud and clay, with occasional low ridges of gravel. During the night in this district we were stopped by a "wash out"; a few hours' deluge of rain having fallen, turned dry channels into roaring torrents, and destroyed the track for some yards in several places. These were rapidly repaired by building up the line with sleepers laid across and across to the required level, and at eight o'clock we went on again; but were again stopped early in the afternoon. Here I strolled about, but it was a miserable desert, with only a few stunted, ugly spiny bushes. Some of the cliffs about were splendid, in strata of red, yellow, bluish, and green. This district is between the Green and the Gunnison rivers, the latter a very turbid stream. Here were a few patches of cultivated land and little rude cabins.

Entering Clear Creek valley the country becomes smoother, the hills more rounded and more clothed with vegetation, like parts of Wales or Scotland, with some pines and cedars. The