368 
ADDITIONAL NOTICES. 
[June 14, 1858. 
his rider, immediately followed by the broom ( Genista ) and heath (Erica). 
These shrubs, however, become more rare and stunted on the plateau of Paul 
da Serra. On the descent towards Oalheta they further diminish, the heath 
becoming the representative plant of that region. As to locality and soil, 
these three species of plants correspond remarkably in their preferences, or 
otherwise, with those of our latitudes. The smallest, the airelle (Racinium 
myrtillus ), seeks the humid shade of the pine forests (Pinus picea) ; the 
heaths delight in the vicinity of the firs (Pinus sylvestris ) ; whilst the brooms 
(Genista tinctoria and pilosa) prefer situations open to the sun.* * * § 
In order to complete the physiognomy of the island, which the map is in- 
tended to reveal, some meteorological indications must be noticed, resulting 
from its configuration. There are but two stations, with observations at which 
we are acquainted : those made at Funchal and in its vicinity we learn from 
the English works of Mason, Clark, White, and Harcourt ; a German work 
lately published t informs us of the results of those made at St. Anne. The 
hygrometric observations confirm what has been stated concerning the vege- 
tation on the different slopes — that those on the north are more humid than 
those on the southern side. Hence it is that the levadas or conduits of water 
are necessary to render irrigation and extended cultivation practicable on the 
southern side of the island. The dominant winds, the north and north-west, $ 
bring damp. Their predominance, however, does not enfeeble the influence 
of the west winds on the vegetation. The valleys of Sao Vicente and Boa 
Ventura are completely open to currents of air from the north, notwithstanding 
their declivities exposed to the west wind are clothed with a more stunted 
vegetation, especially in their upper portions, than are the opposite slopes. 
In the same account, the most extensive laurel woods, and containing the 
largest trees, are seen in the valley of Medada, which is closed on the west 
side. The cultivated lands at greater elevations are liable to the same con- 
ditions^ Even in the Bay of Funchal, where west and north winds are very 
rarely experienced, the banana (Musa paradisiacal) is seen in perfection only 
where it is completely sheltered from them. The same is the case as respects 
the few date-trees (Phoenix dactylifera ) on the south and east coasts. The 
localities suitable to their growth are protected against the west wind ; 
examples in proof of this are seen at Calheta, Ponta do Sol, Camara de Lobos, 
Funchal, and Machico, which places, however, are subject to sea-breezes. 
The pine (Pinus pinaster) bears every current of air ; and there is every pro- 
bability that the upper boundary of its forests marks the limits of its sea- 
breezes in the interior of the island. 
The abrupt rise of the coast in some places from the border of the sea causes 
* Observations on plants which have been introduced, and on the flora of Madeira, 
will be found in the work of O. Heer, ‘ Die periodischen Erscheinungen der 
Pflanzenwelt in Madeira’ (1853). 
t Dr. C. Mittermaier, Madeira und seine Bedeutung als Heilungsort (1855). 
j According to Mittermaier, in 1000 observations — 
The N. wind was found to prevail 256 times — the W. 77 times. 
N.N.W. „ 68 „ N.W. 170 „ 
N.W. „ 88 „ N.N.W. 166 „ 
S. „ 8 „ W. 4 „ 
§ A position analogous to that of Madeira is occupied by the rock of Tristan 
d’Acunha. According to the communications of Captain Denham, r.n. (Nautical 
Magazine, 1853, pp. 183, 188), we may conclude that notwithstanding the variable 
climate there, the s. and s.w. winds bring humidity, as is the case at Madeira 
with n. and n.w. winds. The conditions of the s. and n. coasts are reversed in 
the two islands. It would be interesting to know how far the contrast holds 
good with respect to the vegetation of Tristan d’Acunha. 
