Hearne's Journey, p. 383.
 Maclaren, art. "America," Encyclop. Brittann.
 Azara says, "Je crois que la quantite annuelle des pluies est, dans toutes ces contrees, plus considerable qu'en Espagne." -- Vol. i. p. 36.
 In South America I collected altogether twenty-seven species of mice, and thirteen more are known from the works of Azara and other authors. Those collected by myself have been named and described by Mr. Waterhouse at the meetings of the Zoological Society. I must be allowed to take this opportunity of returning my cordial thanks to Mr. Waterhouse, and to the other gentleman attached to that Society, for their kind and most liberal assistance on all occasions.
 In the stomach and duodenum of a capybara which I opened I found a very large quantity of a thin yellowish fluid, in which scarcely a fibre could be distinguished. Mr. Owen informs me that a part of the oesophagus is so constructed that nothing much larger than a crowquill can be passed down. Certainly the broad teeth and strong jaws of this animal are well fitted to grind into pulp the aquatic plants on which it feeds.
 At the R. Negro, in Northern Patagonia, there is an animal of the same habits, and probably a closely allied species, but which I never saw. Its noise is different from that of the Maldonado kind; it is repeated only twice instead of three or four times, and is more distinct and sonorous; when heard from a distance it so closely resembles the sound made in cutting down a small tree with an axe, that I have sometimes remained in doubt concerning it.
 Philosoph. Zoolog., tom. i. p. 242.
 Magazine of Zoology and Botany, vol. i. p. 217.
 Read before the Academy of Sciences in Paris. L'Institut, 1834, p. 418.
 Geolog. Transact. vol. ii. p. 528. In the Philosoph. Transact. (1790, p. 294) Dr. Priestly has described some imperfect siliceous tubes and a melted pebble of quartz, found in digging into the ground, under a tree, where a man had been killed by lightning.
 Annals de Chimie et de Physique, tom. xxxvii. p. 319.
 Azara's Voyage, vol. i. p. 36.