On the morning of the 17th the clouds had disappeared, and the valley was lit up with brilliant sunshine. Fresh snow lay thickly on the flanks of the higher mountains, and I had reason to congratulate myself that I had not undertaken an expedition which would have resulted in utter discomfort without any adequate compensation, as the Alpine vegetation must have been completely concealed by the fresh snow. The roads and paths were all deep in mud, and the slopes very slippery from the rain, so I decided on descending to the rocky banks of the river below the baths, and, following the stream as far as I conveniently could. I did not go far, but a good many hours were very well occupied in examining the vegetation of the left bank of the Cachapoal and of a little island of rock in the middle of the stream. In summer one of the ordinary suspension bridges of the country enables the visitors to cross to the right bank, but this is removed during winter, and the swollen waters of the river made all the usual fords impassable for the present.
GROUPS OF INCOMPLETE SPECIES.
Many forms of Escallonia were abundant along the stream. A few species only of this genus are cultivated in English gardens, but in their native home, the middle and lower slopes of the Andes, they exhibit a surprising variety of form while preserving a general similarity of aspect. They are all evergreen shrubs, some rising to the stature of small trees, with undivided, thick, usually glossy leaves, and white, red, or purplish flowers. Although forty-three different species have been described from Chili alone, it is easy to find specimens not exactly agreeing with any of them, and to light upon intermediate forms that seem to connect what appeared to be quite distinct species. They afford an example of a fact which I believe must be distinctly recognized by writers on systematic botany—that in the various regions of the earth there are some groups of vegetable forms in which the processes by what we call species are segregated are yet incomplete; and amid the throng of closely allied forms, the suppression of those least adapted to the conditions of life has not advanced far enough to differentiate those which can be defined and marked by a specific name.
To the believer in evolution, it must be evident that at some period in the history of each generic group there must have occurred an interval during which species, as we understand them, did not yet exist; and perhaps the real difficulty is to explain why such instances are not more frequent than they now appear to be. Familiar examples are the genera Hieracium and Rosa in Europe; Aster and Solidago in North America; while in South America, Escallonia, Malvastrum, and several groups of Myrtaceæ seem to exhibit the same phenomenon.
Another genus having numerous species in South America, but, so far as I know, not displaying the same close connection of forms linking the several species, is Adesmia, a leguminous genus allied to the common sainfoin. I found several species near the baths, the most attractive being a little spiny yellow-flowered bush, with much the habit of some Mediterranean Genistæ, but with pods formed of several joints, each covered with long, purple, glistening hairs.
A bright day was followed by a clear cold night, the thermometer falling to 40° Fahr. in the court, and slight hoar-frost was visible in the lower part of the valley near the baths. I started early for a ramble over the higher hills rising to the south and south-west of the establishment. After following a track some way, I struck up the steep stony slopes, meeting at every step the dried skeletons of many interesting plants characteristic of this region of America, but here and there rewarded by finding some species in fruit, or even with remains of flower. After gaining the ridge, I found that the true summit lay a considerable way back, quite out of sight of the baths. To this, which is called El Morro de Cauquenes,[27] I directed my steps, wishing to enjoy a unique opportunity for a wide view of the Chilian Andes.
PANORAMIC VIEW OF THE ANDES.
The day was cloudless, and the position most favourable. In this part of the range the Cordillera bends in a curve convex to the east, so as to describe a nearly circular arc of about 60°, with Cauquenes as a centre. The summits of the main range, which apparently vary from about sixteen to nineteen thousand feet in height, and are nearly forty miles distant, send out huge buttresses dividing the narrow valleys whose waters unite to form the Cachapoal, and are in many places so high as to conceal the main range. The slopes are everywhere very steep, so that, in spite of the recent fall of snow, dark masses of volcanic rock stood out against the brilliant white that mantled the great chain. The tints in Petermann’s map would indicate that the highest peaks are those lying about due east, but it appeared to me that two or three of those which I descried to the south-east, though slightly more distant, were decidedly higher. It will probably be long before the Chilian Government can undertake a complete survey of the gigantic chain which walls in their country on the eastern side. No pass, as I was informed, is used to connect the upper valley of the Cachapoal with the Argentine territory.
From the summit I descended about due north into a little hollow, whence a trickling streamlet fell rather rapidly towards the main valley. As commonly happens in Chili, this has cut a deep trench, or quebrada; and when I had occasion to cross to the opposite bank, I had no slight difficulty in scrambling down the nearly vertical wall, though partly helped and partly impeded by the shrubs that always haunt these favourable stations. The Winter’s bark, not yet in flower, differed a good deal from the form which I had seen at Valparaiso, and the foliage was much the same that I afterwards found in the channels of Patagonia. Among the few plants yet flowering at this season was a large lobelia, of the group formerly classed as a distinct genus under the name Tupa,[28] and which is peculiar to Chili and Peru.