340 
POPULAli SCIENCE KEVIEW. 
sold in the shops roasted, is pleasant enough to eat, is another 
instance. We find, however, that this fruit does not possess 
the usual characteristic of the legume, for the pod in which 
the seeds are inclosed breaks or splits up irregularly. In 
some plants of this family the seeds are undoubtedly un- 
wholesome, if not poisonous, and great care should be taken 
to avoid them: such, for instance, as the common Laburnum. 
The second sub-order of th eLegmninosce is called the Cresal- 
piniece, or the Senna section. It includes only foreign plants. 
They have imbricated petals — that is, petals which wrap over 
each other in the bud, the upper one being in the inside, and 
each petal more closely resembles its fellow than those of the 
Papilionacece. In some cases the petals are absent. The 
plants of this division are chiefly those which are useful in 
dyeing or for medicine — senna, logwood, and the tamarind are 
amongst them ; and, were we attempting to write a complete 
history of the remarkable products of the family Leguminosce, 
we should find in this subdivision alone enough interesting 
matter to fill many pages. In Dr. Lindley’s “Vegetable King- 
dom ” there is given a drawing of one of the Great- Locust trees 
of the West, described by Marti us as belonging to this sub- 
division of Leguminosce, which is of such enormous dimensions 
that fifteen Indians, with outstretched arms, could only just em- 
brace one of them. By counting the concentric rings of such 
parts of the stem as were accessible, Martius concluded that 
some of these trees now existing were of the age of Homer ; 
indeed, several of them were computed to have seen even remoter 
times. It seems almost incredible that the modest little plant 
which we have taken as the representative of this great family 
should claim kindred with these mighty forest trees, and 
become the easiest exponent of their distinguishing charac- 
teristics. 
The third subdivision of the order is called Mimosece, or the 
Gum-Arabic section. It consists chiefly of plants in which gummy 
and astringent matters prevail. The petals are regular andvalvate 
in aestivation, — that is, they do not overlap in the bud. Various 
species of Acacia belong to this section. Acacia forrnosa sup- 
plies the valuable Cuba timber called Sabicu, of which was 
made the stairs of the Crystal Palace in Hyde Park in 1851. 
The astringent substance known as Catechu is furnished by 
several species of Acacia. The Rosewood of commerce, so well 
recorded in our domestic articles of furniture, is produced by a 
species of Mimosa from the forests of Brazil. A species of 
Mimosa is an object of interest in our conservatories and 
greenhouses on account of its sensitive properties. There are 
but few of us who have not been amused with watching the 
closing, shrinking leaves of Mimosa scnsitiva, when touched or 
handled. 
