The Voyage of the Beagle. Darwin Charles

Чтение книги онлайн.

СКАЧАТЬ at three tons and a half; we will call it three. From these premises we may give three tons and a half to each of the five rhinoceroses; perhaps a ton to the giraffe, and half to the bos caffer as well as to the elan (a large ox weighs from 1200 to 1500 pounds). This will give an average (from the above estimates) of 2.7 of a ton for the ten largest herbivorous animals of Southern Africa. In South America, allowing 1200 pounds for the two tapirs together, 550 for the guanaco and vicuna, 500 for three deer, 300 for the capybara, peccari, and a monkey, we shall have an average of 250 pounds, which I believe is overstating the result. The ratio will therefore be as 6048 to 250, or 24 to 1, for the ten largest animals from the two continents.

47

If we suppose the case of the discovery of a skeleton of a Greenland whale in a fossil state, not a single cetaceous animal being known to exist, what naturalist would have ventured conjecture on the possibility of a carcass so gigantic being supported on the minute crustacea and mollusca living in the frozen seas of the extreme North?

48

See Zoological Remarks to Capt. Back's Expedition, by Dr. Richardson. He says, "The subsoil north of latitude 56 degs. is perpetually frozen, the thaw on the coast not penetrating above three feet, and at Bear Lake, in latitude 64 degs., not more than twenty inches. The frozen substratum does not of itself destroy vegetation, for forests flourish on the surface, at a distance from the coast."

49

See Humboldt, Fragments Asiatiques, p. 386: Barton's Geography of Plants: and Malte Brun. In the latter work it is said that the limit of the growth of trees in Siberia may be drawn under the parallel of 70 degs.

50

Sturt's Travels, vol. ii. p. 74.

51

A Gaucho assured me that he had once seen a snow-white or Albino variety, and that it was a most beautiful bird.

52

Burchell's Travels, vol. i. p. 280.

53

Azara, vol. iv. p. 173.

54

Lichtenstein, however, asserts (Travels, vol. ii. p. 25) that the hens begin sitting when they have laid ten or twelve eggs; and that they continue laying, I presume, in another nest. This appears to me very improbable. He asserts that four or five hens associate for incubation with one cock, who sits only at night.

55

When at the Rio Negro, we heard much of the indefatigable labours of this naturalist. M. Alcide d'Orbigny, during the years 1825 to 1833, traversed several large portions of South America, and has made a collection, and is now publishing the results on a scale of magnificence, which at once places himself in the list of American travellers second only to Humboldt.

56

Account of the Abipones, A.D. 1749, vol. i. (English Translation) p. 314

57

M. Bibron calls it T. crepitans.

58

The cavities leading from the fleshy compartments of the extremity, were filled with a yellow pulpy matter, which, examined under a microscope, presented an extraordinary appearance. The mass consisted of rounded, semi-transparent, irregular grains, aggregated together into particles of various sizes. All such particles, and the separate grains, possessed the power of rapid movement; generally revolving around different axes, but sometimes progressive. The movement was visible with a very weak power, but even with the highest its cause could not be perceived. It was very different from the circulation of the fluid in the elastic bag, containing the thin extremity of the axis. On other occasions, when dissecting small marine animals beneath the microscope, I have seen particles of pulpy matter, some of large size, as soon as they were disengaged, commence revolving. I have imagined, I know not with how much truth, that this granulo-pulpy matter was in process of being converted into ova. Certainly in this zoophyte such appeared to be the case.

59

Kerr's Collection of Voyages, vol. viii. p. 119.

60

Purchas's Collection of Voyages. I believe the date was really 1537.

61

Azara has even doubted whether the Pampas Indians ever used bows.

62

I call these thistle-stalks for the want of a more correct name. I believe it is a species of Eryngium.

63

Travels in Africa, p. 233.

64

Two species of Tinamus and Eudromia elegans of A. d'Orbigny, which can only be called a partridge with regard to its habits.

65

History of the Abipones, vol. ii. p. 6.

66

Falconer's Patagonia, p. 70.

67

Fauna Boreali-Americana, vol. i. p. 35.

68

See Mr. Atwater's account of the Prairies, in Silliman's N. A. Journal, vol. i. p. 117.

69

Azara's Voyages, vol. i. p. 373.

70

M. A. d'Orbigny (vol. i. p. 474) says that the cardoon and artichoke are both found wild. Dr. Hooker (Botanical Magazine, vol. iv. p. 2862), has described a variety of the Cynara from this part of South America under the name of inermis. He states that botanists are now generally agreed that the cardoon and the artichoke are varieties of one plant. I may add, that an intelligent farmer assured me that he had observed in a deserted garden some artichokes changing into the common cardoon. Dr. Hooker believes that Head's vivid description of the thistle of the Pampas applies to the cardoon, but this is a mistake. Captain Head referred to the plant, which I have mentioned a few lines lower down, under the title of giant thistle. Whether it is a true thistle I do not know; but it is quite different from the cardoon; and more like a thistle properly so called.

71

It is said to contain 60,000 inhabitants. Monte Video, the second town of importance on the banks of the Plata, has 15,000.

72

The bizcacha (Lagostomus trichodactylus) somewhat resembles a large rabbit, but with bigger gnawing teeth and a long tail; it has, however, only three toes behind, like the agouti. During the last three or four years the skins of these animals have been sent to England for the sake of the fur.

73

Journal of Asiatic Soc., vol. v. p. 363.