From Richard Thomas Lowe1   12 April 18562

12 April ’56

The Flora of Porto Sto. may be stated at from 270 to 280 species (indigs. and perfectly naturalized).3

Of these, 7 or 8 are certainly, and one or 2 others doubtfully endemic—the doubt arising from difficulty of ascertaining identity of species— 3 or 4 of the 7 or 8 are sufficiently striking and abundantly growing plants. 2 or 3 represent Madn. endemic sp: 2 or 3 are more of the nature of “weeds”.

Of plants common to Po So & Mad: but not hitherto found elsewhere, there are 20 or 21, perfectly certain, and 3 others doubtful.

Again, of plants common to Po So. and other countries (mainland) of Europe, but not found at all in Mada. there are 25 certain & 4 doubtful.

Lastly, of plants common to Po So. and other countries (mainland) of Europe, but very rare in Mada. there are 6, to which may perhaps be added 2, which are indeed only at this day occasional garden plants in Mada., whence they were introduced in 1834, into Po. So. which they have now completely overspread! One of these is a Tamarix, (T. orientalis L.?); and the other is the Hottentot Fig, (Mesembryanthemum edule L.)

Of classes 3 & 4, almost all are common European “weeds”, proving of course little any way. And let me add, that the very peculiar nature of the soil & climate of Po. So. as compared with Mada accounts of itself in great measure for the very different character & aspect generally of the vegetation in the 2 Islands. Many plants common in one Island, can not be made by any efforts to grow in the other.

This may be useful as a caution against attributing too much in this particular case to other possible modifying general causes or influences.

Hooker has I think considerably underrated the number of good endemic species in Madeira,4 which exclusive entirely of Po. Stan & Deztan plants will be found I think rather to exceed than fall short of 100. But it would take a good deal more time & research than I can just now afford to speak positively & with accuracy on this head.

There are very many common endemic species in Madeira not occurring in Po. So.

In the Dezertas there are 3 very remarkable endemic common plants, one forming a new genus of Umbelliferae;5 another a new genus of Gramineae;6 the 3d a new shrubby Chrysanthemum, representing C. pinnatifidum L. fil. of Mada..7

There is no freshwater fish in Po So (as in Mada) but the Eel (Ang. latirostris Yarr.) I believe Wollaston & I caught one ourselves in a puddle last spring.

Contemporary copy

1
The original manuscript of this letter has not been found, but there is a copy by Charles Lyell in his ‘scientific journals’ (Wilson ed. 1970, pp. 53–4). Lyell visited CD at Down House from 13 to 16 April 1856, and the ‘Migration of Plants & Shells’ was one of the topics discussed, with particular reference to Madeira, which greatly interested Lyell (Wilson ed. 1970, pp. xlviii–xlvi, 52–5). CD’s notes on their conversation about Madeiran shells, dated 16 April 1856, are in DAR 205.3 (Letters).
2
The date as given by Lyell.
3
CD’s query probably concerned a point he had noted in his copy of A. de Candolle 1855, 2: 801: Could I get list of Naturalised Plants from Lowe for Madeira … This wd be important as showing means of distribution, & as showing inhabitants of islands not well adapted. Lowe was preparing a short catalogue of new species of plants found on Madeira for Hooker’s Journal of Botany and Kew Garden Miscellany (Lowe 1856). The list includes species from Porto Santo, part of the Madeiran group of islands.
4
W. J. Hooker and J. D. Hooker 1847.
5
The genus was called Monizia by Lowe and described in Lowe 1856, pp. 295–6. It comprised only one species, Monizia edulis (a synonym of Daucus edulis), found only on the island of Dezertas.
6
The genus was given the name Arthrochortus and described in Lowe 1856, pp. 301–2. Lowe considered the single species A. loliaceus to be intermediate between the genera Lolium and Lepturus.
7
Chrysanthemum haematomma, described in Lowe 1856, p. 296. It was distinguished from its nearest ally, C. pinnatifidum of Madeira, by the ‘dark blood-coloured florets’.

Please cite as “DCP-LETT-1852A,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-1852A