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not, however, to be had cheaply. I was asked sixty dollars for one at Buenos Ayres, and that, I believe, is about the ordinary price.

The change of weather which culminated in this wet day at Cauquenes seems to have extended along the range of the Cordillera ; but, to illustrate the rapid change of climate which is found in advancing northward along the west side of the Andes, I may mention that, while the rain continued to fall steadily for ten and a half hours at Cauquenes, it lasted but five hours at Santiago, about fifty miles to the northward; and at Santa Rosa, forty miles farther in a direct line, only two hours' rain was obtained by the thirsty farmers on the banks of the Aconcagua.

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

GROUPS OF INCOMPLETE SPECIES.

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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.

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

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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 yellowflowered 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 southwest 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, * I directed my steps, wishing to enjoy a unique opportunity for a wide view of the Chilian Andes.

* The Baths of Cauquenes are said to be 2523 feet above the sea ; the Morro, by aneroid observation, is about 2000 feet higher.

PANORAMIC VIEW OF THE ANDES.

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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,* and which is peculiar to Chili and Peru.

* As happens with many other plants described by early botanists, there has been much confusion in regard to the species named by Linnæus Lobelia Tupa. The plant was first made known to Europeans by the excellent traveller, Father Feuillée, whose “ Journal des Observations Physiques Mathématiques et Botaniques faites sur les côtes de l'Amérique meridionale, etc.,” published in 1714, is a book which may still be consulted with advantage. His descriptions of plants are usually careful and accurate, but the accompanying plates all ill-executed and often misleading. Linnæus, followed by Willdenow, refers to Feuillée’s work, but gives a very brief descriptive phrase which suits equally well Feuillée's plant and several others subsequently discovered. Aiton, in the “ Hortus Kewensis,” gives the name Lobelia Tupa to a plant which is plentiful about Valparaiso, where I found it still in flower, the seeds of which were received at Kew about a century ago from Menzies. This is now generally known by the not very appropriate name Tupa salicifolia of Don, but was first published by Sims in the Botanical Magazine, No. 1325, as Lobelia gigantea, which name it should now bear. The plant which I found near Cauquenes appears to be the Tupa Berterii of Decaudolle, a rare species, apparently not known to the authors of the “Flora Chilena.” No doubt could have arisen as to the plant intended by Linnæus as Lobelia Tupa if writers had referred to Feuillée's full and accurate description. His account of the poisonous effects of the plant was probably derived from the Indians, and may be exaggerated. The whole plant, he says, is most poisonous, the mere smell causing vomiting, and any one touching his eyes after handling the leaves is seized with blindness. I may remark that the latter statement, which appears highly improbable, receives some confirmation from the observations of Mr. Nation, mentioned above in page 77. The plant which I saw in Peru, but failed to collect, is much smaller than most the Chilian species, and has purple flowers, but is nearly allied in structure. It is probably the Tupa secunda of Don. I gather from a passage in one of Mr. Philippi's writings that the word tupa in Araucanian signifies poison. We are yet, I believe, ignorant of the

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