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 a good many uncomfortable horrors taken out of our minds, by the judicious doctor.—"Mayfair."

A Botanical Usurper.—One of the most curious instances on record of the invasion of a country by a plant of foreign origin, and the extermination by it of indigenous species, is seen in the history of the mango tree in the island of Jamaica, as recounted by Sir Joseph Hooker. It reminds us of the accounts of captured tribes which after being carried into their conquerors' country have so increased and multiplied as eventually to dispossess and supplant their captors. In 1782 Admiral Rodney captured a French ship bound for San Domingo from Bourbon, with living plants of the cinnamon, jackfruit, and mango, sent to the Botanic Garden of the former island by that of the latter. The prizes were presented by the Admiral to the Jamaica Botanic Garden. There the cinnamon was carefully fostered, but proved to be difficult of culture in the island; while the mango, which was neglected, became in eleven years as common as the orange, spreading over lowlands and mountains from the sea-level to 5,000 feet above it. On the abolition of slavery immense tracts of land, especially coffee plantations, relapsed to a state of nature, and, the mango being a favorite fruit with the blacks, its stones were flung about everywhere, giving rise to groves along the roadsides and around the settlements; and the fruit of these again, rolling down hill, gave rise to forests in the valleys. The effect of this spread of the mango, Sir Joseph Hooker adds, has been to cover hundreds of thousands of acres, and to ameliorate the climate of what were dry and barren districts by producing moisture and shade, and by retaining the rainfalls that had previously evaporated; all this, besides affording food for several months of the year to both negroes and horses.

Explorations in Central Africa.—Two French travelers, M. Savargnan de Brazza and Dr. Ballay, have returned to Paris after a three years' exploration of the Ogowé (or Ogobai) River. In August, 1875, the travelers left Lambarene, the extreme limit of the European factories, and, escorted by twelve Laptots, or native African soldiers of the French colony of Senegal, explored the river to its sources. One result of the expedition is to prove that the Ogowé does not rise in an interior lake. The river may be divided into three nearly equal parts—the upper, the middle, and the lower. The middle follows an almost straight east and west course just south of the equator; the two others incline about a degree and a half toward the south. The first halt was made at Lopé, a large village on the upper Ogowé. M. de Brazza penetrated into the country of those noble cannibals, the Fans, with whom he entered into friendly relations, and succeeded in reaching Dumé, a position considerably advanced on the upper river. He suffered seriously in this journey, and on his return had to let his companions advance to Dumé without him; he was only able to rejoin them in April, 1877. Through great hardships and dangers they made their way to the Pubara Fall, above which the Ogowé becomes an inconsiderable stream.

After a few days' rest here, the explorers left the basin of the Ogowé in March, 1878, to penetrate still farther into the interior. They traversed successively the territories of the Ondumbo, the Umbeté, and the Bateké, suffering greatly on the way from both hunger and thirst, for the country was devastated by famine. A stream running east, the N'Gambo, led the explorers to an important river, the Alima, 500 feet wide and sixteen feet deep, apparently an affluent of the Congo. In attempting to descend the Alima they had to run the gantlet between banks lined with hostile savages. They quitted the river and marched northward, crossing many watercourses flowing eastward. They suffered so much from hunger that the expedition had to be divided, Dr. Ballay and one of the attendants being sent back to the Ogowé. M. de Brazza went some distance farther northward, when hunger and suffering compelled him also to retreat, and he rejoined his comrade in September. On November 30th the whole party reached the French settlement at the Gaboon.

From Corisco Bay, on the west coast of Africa, and a little north of the mouth of the Gaboon, comes intelligence of certain important explorations made by Hugo de Koppenfels, who reports that he ascended the Muni, the Noya, the Balinji, and the