rLOIL\ OF THE ISTimUS OF PANAMA. 115" 
" Among tliosc plants which, by tlieir beauty and elegance, attract our attention, the genus Acadia 
occupies a prominent place. Few genera are richer in really beautiful fomis,, or possess a greater number 
of truly ornamental species. Their graceful branches, their airy foliage, their numerous, often fragranl 
flowers, have made them favourites with all those who are sensible to the charms of the Vegetable Kingdom. 
Especially the Acacias called Phi/llodinece, are by their habit, their curiously-shaped leafstalks, and their 
diversified colour, even if destitute of flowers, objects of particular interest ; and although the species with 
piimated leaves do not rank so high in this respect, they are nevertheless not destitute of grace or 
beauty. The Acacias, however, do not deserve attention merely on account of their beauty, but also 
on account of their useful properties: many of their products arc necessaries of life, or scnc as ariicles 
of luxury. In commerce, in medicine, and in different handicrafts, they play an important part. Some 
yield a gum used as food by several wild tribes, or employed for technical purposes ; others, distinguished 
by tQnic and astringent (lualitiea, are suited for medicine and for tanning ; others again, abounding in 
odorous principles, furnish valuable ingredients for the manufacture of perfume, while again a great 
number produce fine and durable wood, equally adapted for ornamental furniture and coarse architectural 
works. 
" The genus Acacia, although now considerably circumscribed, contains, aa fiir as our present knowledge 
enables us to state, about 400 species. Their horizontal distribution is limited to the tropical and sub- 
tropical parts of Asia, Africa, America, and Australia. The most northern species, A. Itirta, Nutt, is 
found under the 35th degree of north latitude; the most southern, A. bossicsoides, Benth., under the 42nd 
degree of south latitude. The I'Jii/UodinecE are chiefly confined to New Holland and the adjacent islands ; 
only one species, A. lieteroplylla, AVilld., is met with to the north of the Equator in the Hawaiian group. 
The pinnated species are scattered over Asia, Africa, America, and Australia ; they are however moat 
numerous in America, and, according to a rough calculation, twenty-nine arc found in Australia, thirty in 
Asia, thirty-five in Africa, and sixty-six in America. The vertical distribution of the genus is, in the 
equinoctial region, about 7000 feet abo^■e the level of the sea ; in the temperate zones it is considerably less ; 
those species however which seem to bear the greatest degree of cold are A. bossireoiJes, Benth., and A. 
■mollissima, Willd. ; they grow in the southern parts of A'an Diemen's Land at an elevation of from 3000 to 
4000 feet above the sea. 
" Generally speaking, the Acacias are very local ; only a few arc diff'uscd over a great extent of countrj', 
and still fewer enjoy a wide distribution. Perhaps the most common is Acacia Farncsiana, which has 
followed man on his wandering through the tropics, and is now to be met with almost everywhere in the 
vicinity of human habitations. Several of the Austrahan species have become perfectly natui-alizcd at the 
Cape of Good Hope, and impart to some districts of that country a peculiarly foreign air. Acacia longiJhUa 
covers nearly one-thii-d of St. Helena, where it thrives in such luxuriance that, if its origin was not known 
from historical sources, one might be inclined to consider it a true native of that island. 
" The Acacias are very sociable. AYoods are entirely formed of them, an additional reason ^^\iy 
those species possessing commercial value are so important. Several of the shadcless forests of New 
Holland—the bane of travellers— are composed of Acacias, the phyllodia of which, like the leaves of many 
other Australian plants, being placed horizontally, and thus not presenting any suri-ace, admit the rays of 
the sun. On the whole the Acacias seem to prefer sunny, exposed situations, and a stony, sterile soil. 
They are but seldom met with in damp and sheltered positions, and some of the species, which may 
have been accidentally transported to such places, change their habit to an extraordinary degree, and 
even in their youth become unhealthy. Eor instance, Acacia spadlcigera, Cham, et Schlecht., which, in its 
natural habitat, is a regular pyramidal tree, producmg abundance of blossoms, becomes, on the banks of 
rivers whither its seeds are occasionally swept by the heavy tropical rains, an ugly straggling shrub, which 
^ + 
seldom bears flowers, and still more seldom fruit." 
p 2 
