1
For a list of the plants collected here, see a paper in the Journal of the Linnæan Society, vol. xxii.
2
Much cinchona bark, coming from the interior, was formerly shipped at Tumaco; but between horrible roads and the reckless waste of the forests through mismanagement, but little is now conveyed by this way.
3
For a list of the species collected, see the Journal of Linnæan Society, vol. xxii.
4
The abrupt change in the vegetation on this part of the American coast has been noticed by Humboldt, Weddell, and other scientific travellers. In a note to the French edition of Grisebach (“Vegetation du Globe,” traduit par P. de Tchihatcheff, ii. p. 615), M. André expresses the opinion that this, as well as some other cases of abrupt change in the vegetation observed by him in Colombia, are to be explained by the nature of the soil, which in the arid tracts is sandy or stony, and fails to retain moisture. Admitting that in certain cases this may afford a partial explanation of the facts, it is scarcely conceivable that the limit of the zone wherein little or no rain falls should exactly coincide with a change in the constitution of the soil, and I should be more disposed to admit a reversed order of causation, the porous and mobile superficial crust remaining in those tracts where, owing to deficient rainfall, there is no formation of vegetable mould, and no accumulation of the finer sediment forming a retentive clay.
5
The only detailed account of the operations that I have seen is in a work entitled, “Histoire de la Guerre du Pacifique,” by Don Diego Barros Arana. Paris: 1881. It appears to be fairly accurate as to facts, but coloured by very decided Chilian sympathies.
6
The heights given in the text are those of the railway stations.
7
Of 138 genera of Helianthoïdeæ 107 are exclusively confined to the American continent, 18 more are common to America and distant regions of the earth, one only is limited to tropical Asia, and two to tropical Africa, the remainder being scattered among remote islands – the Sandwich group, the Galapagos, Madagascar, and St. Helena.
8
In Nature for September 14, 1882.
9
The only accurate information that I have found respecting the climate of Lima is contained in a paper by Rouand y Paz Soldan, “Resumen de las Observaciones Meteorologicas hechas en Lima durante 1869,” quoted in the French translation of Grisebach’s “Vegetation du Globe.” Reduced to English measures, they give the following results: —
There is reason to think that the temperature for July, 1869, given above was exceptionally low, and although the months during which fogs prevail are abnormally cool for a place within 13° of the equator, I believe that the thermometer rarely falls below 60° Fahr.
10
See Appendix A, On the Fall of Temperature in ascending to Heights above the Sea-level.
11
It is a curious illustration of the utterly untrustworthy character of statements made by unscientific travellers to read the following passage in a book published by a recent traveller in South America, who visited Chicla in November, the beginning of summer. He declares that the fringe of green vegetation “dwindles and withers at a height of nine or ten thousand feet;… while on the upper grounds, where sometimes rain is plentiful, the air is too keen and cold for even the most dwarfish and stunted vegetation to thrive.”
include more than an equal proportion of species. I find, indeed, that fully sixty per cent. of the species in my collection belong to European genera, but that, with trifling exceptions, the species are distinct and confined to the Andean region. The reasonable conclusion is that the types which are thus common to distant regions must be of very great antiquity, and that the ancestors of the existing species must have spread widely at a very remote period of the world’s history. Most of the plants in question belong to genera having very numerous species, of which it may be presumed that the parent forms possessed a strong tendency to variation.
