Mountain Home bulletin. (Mountain Home, Idaho) 1888-1889, 1889-05-18
:. ABOUT BIRDS EGGS.
interesting Facts Concerning Their Com
pOsitiOn and Formation.

Interesting Facts Concerning Their Com.
position and Formation.
Eggs are composed of two principal
parts, termed, from their color, the
yelk or vitellus, and the white or al
bumen. The latter does not exist IN
the Ovarium or egg-bag; there, as we /
may see in almost every fowl that /.
comes to the table, is also a numerous {
collection of yelks of various sizes. I
When these are fully developed, they {
drop, one by one, through passage {
termed the oviduct into the uterus, in
which the egg is perfectly formed, hav-
Ing collected its albumen or white and
its calcareous she'll, and from which it
is ultimately expelled.
The very expeditions growth or pro-
duction of the white of the shell is an
extraordinary exertion of nature-a
very few hours only being sufficient to
produce it. The texture of the shell is
admirably calculated for preserving
the contained parts, and for retaining
the heat that is conveyed to them by
incubation. Immediately under the
shell is the common membrane which
lines the whole cavity Of the egg, ex-
cept at its broad end, where there is a
small space filed with air. Within
this membrane, the white, which is said |
to be of two kinds. is contained; and
near its centre, in an exquisitely fine
membrane, is the yclk, which is spheri-
cal, while the white is of the same
form as the shell. At each extremity
of the yolk. corresponding with two
ends OF the egg, is the chalaza, a white
firm body, consisting of three beadlike
globules, and it is at these points that
the several membranes are connected.
by which means. in whatever position
the egg may be placed, its various parts
are retained in their proper place.
Near the middle Of the yelk is
small, fat, circular body, named the
cicatricula, in which the rudiments of
the future chick are contained; and
from these, in consequence Of incuba-
tiOn, or from a certain degree Of con-
tinued heat Of any kind. the bird is ul-
timately hatched. In this process the
germinal membrane, as it is called, or
rudimental parts Of the chick, is OBJ
served to become separated into three
layers, from the external layer of which
are formed subsequently the osseous
and muscular systems, and the brain,
spinal cord and nerves; while from the
middle and internal layers are formed
respectively the heart and blood ves-
sells, and the intestinal canal and its
appendages. The yelk and white of
the egg gradually become thinner. sup
plying the growing chick with nourish-
ment, which, increasing in magnitude,
at length bursts its cell and comes
forth, still retaining in its intestines a
portion of the yelk to serve for its sup.
port until its powers are sufficiently
vigorous to enable it to digest extrane-
Gus food.
1t is remarkable fact, that those
birds, the nests of which are most un
covered. and the eggs of which are
most exposed to the sight of their enc
mics, lay them of a color as little diff
ferent as possible from surrounding
objects, so as to deceive the eyes of de
structive animals; whilst, on the con
trary, those birds, the eggs of whicl
are Of n deep and vivid color, and con
sequently very liable to strike the eye
either hide their nests in hollow trees
or elsewhere, or do not quit their egg
except at night, or commence their in
cubation Immediately after laying.
must, moreover, be remarked, that il
those species, the nests of which ar
ft.a l1,oo o1n oit 4 h
eggs without being relieved by the male
these females have generally differen
color from that of the male, and NOR
in unison with neighboring objects.
Pure white, the most treaoherous {
cOlors, we find to be the color of tn
eggs of birds which build in holes, a
the woodpeckers, the kingfshers tn
swifts, the dock and water swallow.
and others; also of those birds, as th
titmice and wrens, which construt
their nests with openings so small thf
their enemies can not see into then
Moreover. we find eggs white in bird
which do not quit their nests. excel
at night, as the owls; or for u Yer
short time during the day, as the fa
cons. Finally, this color Is found
those which lay only one or two egg
and which Immediately begin to sit, {
the pigeons, etc.
The clear green or blue color
proper to the eggs Of many specie
which build in holes. as the startling
the fly-catchers, etc; it is also commo
to the eggs Of birds the nests of whic
are constructed Of green moss, or sit'
ated in the midst of grass. but alway
we'll hidden. Green eggs, too are foun
with many powerful birds able to d
fend them, rs the herons.
A faint green color. approaching
a yellowish tint, Is observed in IL
eggs OF birds, as the partridges al
pheasants, which lay in the grass, wit
out preparing regular nest. The san
color is remarked in those which COW
their nests when they leave them.
the swans and the ducks.-N. Y. LIE
ger.
Your story, Mr.. Winterkill, = "a
the magazine editor to the rising your
Uall |