inhabiting Tropical Africa, while the diversity diminishes as we recede, until districts of greater territorial extent are inhabited by but a single race.

Again, some accordance may be found in the history and habits of the Arab tribes, holding, as they do, the country interposed between the heart of Africa and extensive and important seats of population; while these are occupied in regular succession by pastoral and agricultural nations. The disowning, too, by the Desert tribes, of such individuals as take up agricultural pursuits, looks very like the incipient extension of population.

There is something, also, in the fixed condition of the African tribes, on which Time, in some instances, seems scarcely to make an impression; something in the near approach to the absence of Invention, or of the spontaneous evolution of knowledge; something in the seeming yielding of civilisation before barbarism; and in the bounds prescribed to ambition, from the general failure of attempts to colonise this continent;-Africa, under various guise, having been always sending forth streams of population, and at the same time prohibiting a return.

CHAPTER XXI.

INTRODUCED ANIMALS AND PLANTS OF AMERICA.

AMERICA, when first visited by Europeans, appears to have contained but a single species of quadruped of foreign origin, the domestic dog. The route of its introduction is indicated by various circumstances; such as the aboriginal use of this animal for draught on both sides of Behring Straits, and the interweaving of the hair in blankets by the neighbouring maritime tribes. We shall find, moreover, a geographical coincidence; for, according to the presumed order of human migrations, all foreign animals, wheresoever occurring in aboriginal America, should be equally in the possession of the North-western tribes.

a. Plants of Aboriginal Introduction.

Independently of the usual habits of sea-going people, the latitudes above referred to preclude agriculture; and we have thus a ready explanation of the absence of this art from the adjoining more southern portion of the American continent; for, until the recent visits of foreigners, "no Oregon native had ever thought of planting a seed." It is clear, then, that no cultivated plant was introduced into America by this northern route: but we cannot speak so positively in regard to weeds. I found two weeds growing abundantly around the Chinook villages, Polygonum aviculare, and Chenopodium album and Mr. Brackenridge met with a third, Plantago major, in the secluded district of Gray's Harbour.

Further south, I discovered some doubtful appearances of aboriginal agriculture on the Sacramento River, in a bed of the chilicoyote or wolf-poison," Cucurbita fætidissima?, growing near a native village: as, however, the plant did not seem to be valued (the natives making no objection to my taking the fruit), it may have been merely naturalised. I did not meet with any other weeds growing around the native villages of the Upper Sacramento; but Solanum nigrum was occasionally seen on the river bank.

In the eastern part of America, both within and for a considerable distance without the Tropics, agriculture is known to have

existed aboriginally; and, moreover, some of the objects of cultivation appear to have been derived from abroad. The latter point is of importance; for it may be, after all, that agriculture was not of spontaneous development in America.

In the aboriginal condition of America the indigenous domestic animals and plants seem to have been principally and separately confined to the two centres of civilisation, Mexico and Peru: the lama and the Peruvian cultivated plants had not reached Mexico; while the Mexican cochineal, agave, and tobacco had not reached Peru. On the other hand, the plants which seem to have been aboriginally derived from abroad were much more generally diffused, as in the corresponding instance of the dog.

The plant most widely cultivated in aboriginal America is the maize, or Indian corn. If it shall prove foreign, there is but one route open to its introduction, that of Japan. It is further manifest, from the local absence of the plant, that North California was not the point of dissemination to other parts of America.

I met with specimens of aboriginal cotton at the ancient Peruvian cemetery of Pachicamac. The species differs from the Poly nesian, and is perhaps peculiar; though the plants of this genus are sufficiently hardy to have been derived through Japan. We have, moreover, a direct tradition (mentioned by Humboldt) that the culture in Mexico of both cotton and maize was taught by the Toltecas.

Cloth dyed blue, apparently with indigo, was also found at Pachicamac. The manufacture of indigo could not have been derived through the Polynesian islands. It should also be observed that there are indigenous species of indigo plant in America.

Specimens of the small-fruited variety of gourd, which is still common in the market of Lima, were exhumed at the same ancient cemetery. I did not see the plant growing. The Lage naria vulgaris is a hardy tropical plant, that could have been introduced either through Japan or through the Polynesian

islands.

The sweet potato (Convolvulus batatas) is equally hardy in its constitution, and could have been introduced either by the route of Japan or that of the Polynesian islands.-The_Portuguese Pilot (who set out in A. D. 1520 on his voyages to the colony at St. Thomas, in the Gulf of Guinea) speaks of this plant, and states that it is called "batata" by the aboriginals of St. Domingo.

The Capsicum is sufficiently hardy to have been introduced by the route of Japan;

And so is Physalis edulis,

And Solanum nigrum: though the most convenient route for the three last-named plants is that of the Polynesian islands.

On the other hand, the banana is too strictly tropical in its

constitution to have been derived through Japan. The two American varieties, it may be observed, were not seen at the Polynesian islands.

The Carica papaya likewise requires a tropical route; and it could have been conveniently introduced through the Polynesian islands:

The same remark will apply to the cocoa palm.-I am not sure that this plant is of aboriginal introduction; but Oviedo (who was personally acquainted with some of the companions of Columbus, and who commenced writing in A. D. 1525) mentions the presence of cocoa palms in the West Indies.

Ageratum conyzoides, perhaps an aboriginal weed, likewise requires a tropical route for its introduction.

b. Animals and Plants recently introduced into Northwest America.

I shall mention, in the first place, the animals and plants which have been fairly imparted, and have attached themselves to the aboriginal tribes of Oregon:

Horses were found by Lewis and Clarke among the tribes of Interior Oregon, having been derived from the Spaniards of New Mexico. It seems, therefore, the more remarkable that horses have not been acquired by the wild tribes of the Sacramento.

Helianthus, an annual species, and the only weed I saw growing around the native villages of Interior Oregon, was perhaps aboriginally introduced from the southward. I met with the same plant, however, at the California settlements.

Pectocarya penicillata (a Boragineous plant) was seen on the north branch of the Columbia River, growing as a weed around Fort Okonagan, a post where the soil is not cultivated. The plant may have accompanied the cattle from the Lower Columbia and its history seems connected with that of the preceding plant. Moreover, these two were the only introduced plants I could discover growing around Fort Okonagan.

Solanum tuberosum. The French Catholic missionaries and the Hudson Bay Company have imparted the cultivation of the potato to the Chinooks of the Straits of De Fuca. The potato was also seen cultivated at one native village on the north branch of the Columbia.

The other plants and animals introduced by the Hudson Bay Company were found to be confined to the immediate environs of Forts Colville, Nisqually, and Vancouver, and to the agricultural settlements on the Willamette and Cowalitz. The plants under cultivation at the two first-named places were few, and were not specially noted; but at Vancouver an extensive and well-conducted garden had been established for many years. The original

packages of seeds were brought, some by sea, but chiefly overland from Montreal.

Bullocks were introduced into Oregon some years prior to our visit.

Sheep were of somewhat later introduction.

Chenopodium album, already mentioned as perhaps an aboriginal weed.-Is yet, possibly, of European introduction. It was seen in the cultivated ground at Forts Nisqually and Colville, and, unlike the following plants, widely spread over the adjoining prairie.

Plantago major, also mentioned as perhaps an aboriginal weed. -The plant was seen naturalised in pathways at Fort Colville. Polygonum aviculare, also mentioned as perhaps an aboriginal weed, and observed growing in beds around the Chinook villages. -The plant was seen naturalised around Fort Colville; but at Fort Nisqually I met with the broad-leafed variety only.

Polygonum nigrum was seen established in the cultivated ground at Fort Colville.

Anthemis cotula had become an abundant weed around Fort Colville.

Amaranthus, a weed in the cultivated ground at Fort Colville. A species, perhaps the same, was seen at the Kooskoosky station. Capsella bursa-pastoris, a weed at Fort Colville. A single specimen was found at Fort Nisqually.

Sonchus oleraceus, a weed in the garden at Fort Nisqually.

Poa annua, observed both at Fort Nisqually and at some of the posts in the Interior.

Triticum sativum, wheat, hardly succeeds at Fort Nisqually; but it was said to be cultivated to some extent on the Willamette and Cowalitz. Three or four varieties were seen at Fort Colville, whence they had been transferred to the Kooskoosky station. Hordeum vulgare, barley; together with

Avena sativa, oats; and

Secale cereale, rye, were observed by Mr. Brackenridge under cultivation at Fort Vancouver.

Pyrus malus, the apple, was said to produce abundantly at Fort Vancouver. But fruit-trees could hardly be cultivated at Fort Colville, on account of the ravages of the small marmot.

Pyrus communis, the pear. The tree was seen by Mr. Brackenridge under cultivation in the garden at Fort Vancouver, together with

Vitis vinifera, the European grape ;
Amygdalus Persica, the peach;

Armeniaca vulgaris, the apricot ;

Prunus domestica, the European plum;

Prunus cerasus, the European or the common garden cherry ;