BOTANY. 
fruit of the pea kind, solitary, formed of 
two oblong valves, without any longitudinal 
partition, and having the seeds ranged along 
one of its margins only. 4. Drupa, fig. 43, 
a stone-fruit, like the peach and cherry, has 
a fleshy undivided coat, containing a single 
hard stone or nut. 5. Pomum , fig. 44, an 
apple, contains a capsule of several cells in 
a fleshy coat. 6. Baccu, fig. 45, a berry, is 
fleshy, without valves, containing one or 
more seeds lodged in pulp, as the gooseber- 
ry and currant. Some berries are com- 
pound, as the raspberry ; others are of a spu- 
rious kind, the pulp originating from some 
part not properly belonging to the truit, 
as the calyx in the mulberry, and the 
receptacle in the strawberry. And, fig. 4-6, 
Strobilus, a cone, originates from a catkin, 
become hardened, and enlarged into a com- 
pound seed-vessel, as in the fir, birch, &c» 
6. Semina, the seeds, fig. 47, the most es- 
sential of all the organs of fructification, be- 
ing those to which ail the others are subservi- 
ent. Theseeds are composed of several parts, 
the most important of which is the embryo, 
or germ. Linnaeus calls it corculum , a little 
Sieart, in allusion to its shape in the walnut, 
in which, as well as in the bean, and other 
leguminous plants, it is readily observed. 
Its position is either upright, horizontal, or 
reversed. It is generally lodged within the 
substance of the seed, except in grasses. 
Cotyledones, the cotyledons, or seed-lobes, 
are intimately connected with the embryo : 
they are almost universally two in number, 
though in the fir tribe they are more nu- 
merous. When the seed has sent its root 
into the ground, these organs generally rise 
above the surface, and perform the functions 
of leaves till the proper foliage is produced. 
Plants, therefore, for the most part are pro- 
perly denominated dkotyledtm.es. Such as 
are called monocoiyledon.es have really no 
proper cotyledon, and the first part that 
appears above the ground from their seed is 
a real leaf. Albumen, the white, makes up 
the chief bulk of some seeds; but never 
rises out of the ground, nor assumes the 
office of leaves, being destined solely to 
nourish the embryo till its roots can perform 
their office. It may be observed in grasses, 
corn, and palm-trees : in some it is farina- 
ceous ; in others as hard as a stone, witness 
the date. The nutritious matter, which in 
these plants Constitutes the albumen, is in 
othersJodged in the substance of the coty- 
ledons. VileUus, the yolk, was first named 
by Gaertner, and is supposed by him to 
furnish nourishment to the embrvo. Dr. 
VOL. I. 
Smith, however, has first suggested that 
the vitellus is rather a subterraneous coty- 
ledon, see his “ Introduction to Botany,” 
292. Testa, the skin, a single or double 
membrane envelops the parts hitherto de- 
scribed, bursting irregularly when its con- 
tents swell in germination, llilum, the 
scar, is the point of attachment through 
which nourishment is conveyed to the seed 
while growing. This point is always consi- 
dered as the base of the seed in description. 
Seeds are often accompanied by appen- 
dages or accessory parts, as pellicula, t'ne 
pellicle, which adheres to their outside in 
the form of a fine skin, sometimes downy, 
sometimes of a mucilaginous substance. An 
instance of the latter occurs in Salvia ver- 
benaca, whose seeds are celebrated for ex- 
tracting particles of dust from the eye, by 
enveloping them in its mucilage, which 
swells on the application of moisture. Aril- 
lus, the tnnic, is a complete or partial co- 
vering of a seed, fixed to its base only, and 
more or less closely enfolding its other 
parts. In the euonymus it is pulpy aud 
orange-coloured, the seed itself being crim- 
son. The mace which enfolds the nutmeg 
is of this nature. Many of the orchis tribe 
are enveloped in a membranous tunic, ex- 
tending beyond the outline of the seeds, apd 
giving them a light'chaffy appearance. The 
elegant wood-sorrel has an elastic arillus, 
like a little bag, serving to project the seeds 
to a distance. In the carex the same part is 
in some degree inflated and membranous. 
The covering of the seeds in the cynoglossum 
is considered by Dr. Smith as. a testa rather 
than an arillus. Pappus, the seed-down, in 
its most strict sense, is the chaffy, feathery, 
or bristly crown of several seeds that have 
no seed-vessel, as in the dandelion, thistle, 
scabious, and others. In a more general 
sense pappus is applied to any feathery or 
downy appendage to seeds, even though 
lodged in a pericarpimn. Cauda, a tail, is an 
elongated appendage, originating from the 
permanent style. It is generally feathery, 
as in the virgin’s bower, clematis. Ros- 
trum, a beak, has a similar origin, but usual- 
ly belongs to a seed-vessel. Ala, a wing, is 
a dilated membranous appendage, serving 
to waft seeds along in the air. To all the 
above may be added various spines, hooks, 
scales, and crests, generally serving to at- 
tach such seeds as are furnished with them 
to tlie rough coats of animals, and so to pro- 
mote their dispersion. This appears to be 
the final purpose of the awns of grasses io 
general. 
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