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new organization, but also a quantity of aliment laid up for its early nou¬ 
rishment. 
The eggs of birds contain two kinds of albumen, or white, one less 
viscid than the other, which is first consumed, and the yolk or vitellum, 
which is drawn up into the bowels of the chick at its exclusion from the 
shell, and serves it for nourishment a day or two, till it can learn to select 
and digest grains or insects. In like manner many seeds are furnished 
with two kinds of nourishment, the mucilaginous or oily meal of the seed- 
lobes, and the saccharine or acescent pulp of the fruit, as in pears, plums, 
and cucumbers, which supply nutriment to the embryo plant, till it is able 
to strike into the earth sufficient roots for the purpose of absorbing its 
nutritious juices. 
The spawn of fish, and of frogs, and of insects, as of snails and bees, 
which are almost as innumerable as the seeds of plants, and are in the same 
manner excited into life by the warmth of the sun, are analogous to those 
seeds, I believe, which are not surrounded with fruit, and which contain but 
one kind of nourishment for the embryo plant, as grains of corn, and 
legumes; but perhaps these have not yet been sufficiently attended to by 
philosophers. 
These eggs of animals and seeds of vegetables are produced by the con¬ 
gress of male and female organs; the former supplying the speck of anima¬ 
tion or cicatricula in the egg, and the corculum or heart in the seed; and 
the latter producing the nidus, or nest for its reception, and the nutritive 
material for its first support. Thus the eggs of fowls are formed long before 
they are impregnated, and are sometimes laid in their unimpregnated state; 
and the seeds of legumes are visible many days before the flower opens, and 
in consequence before they are impregnated, as before observed. 
The eggs of birds contain a bag of air at their broad end for the pur¬ 
pose of oxygenating the blood of the chick. In this one circumstance the 
seeds of plants seem to differ from the eggs of birds, as they contain no 
air-bag, though it is probable they may agree with the spawn of fish, which 
I suppose possess no included air. When the seeds fall on the ground in 
their natural state of growth, or are buried an inch or two beneath the soil, 
which has recently been turned over, and thus contains much air in its 
interstices, their coats do not continue dry dike the shells of eggs during 
incubation, but immediately become moist membranes, like the external 
membrane of the spawn of fish immersed in water, and in consequence can 
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