Egg sac

“ If the yolk be removed and dried, and the yellow oil separated, it will be found to form two-thirds of the substance. The whole weight in its natural state is about three hundred grains, of which three-fifths is water; of the white more than three quarters is water.
The yolk and albumen of a fecundated egg remains as sweet and free from corruption during the whole time of incubation as it is in new-laid eggs, and there is but little loss of water; whereas an unfecundated egg passes rapidly into putrefactive decay and perishes. ”

“ It is difficult to fix the exact term during which the vitality of an egg remains unextinguished; as it, unquestionably, varies from the very first, according to the vigor of the parents of the inclosed germ, and fades away gradually till the final moment of non-existence. The chickens in stale eggs have not sufficient strength to extricate themselves from the shell; if assisted, the yolk is found to be partially absorbed into the abdomen, or not at all; they are too faint to stand; the muscles of the neck are unable to lift their heads, much less to peck ”

“ The little creature which has just pecked its way out of its calcareous prison-house, has lime and phosphorus in his bones, sulphur in his feathers, iron, potash, soda and magnesia in his blood, all of which mineral constituents come from the egg, and are taken into the stomach when it is eaten as food.
The valuable or important salts are contained in the yolk, and hence this portion of the egg is the most useful in some forms of disease. A weakly person, in whom nerve force is deficient and the blood impoverished, may take the yolks of eggs with advantage. ”

“ As fast as the female deposits her eggs, the male who attends her arranges them on her broad [Pg 328] back, to the number of fifty or upwards. The contact of these eggs with the skin appears to produce a sort of inflammation; the skin of the back swells, and becomes covered with pits or cells, which enclose each a single egg, the surface of the back resembling the closed cells of a honeycomb. ”

“ The organ to which these are attached is the ovary. The smallest yolks are so small that they cannot be seen without a powerful microscope. These yolks are not germs, but as they grow the germ forms on one side of each yolk, where it appears as a small white spot.
When a yolk is full-grown it drops into the funnel-shaped mouth of the oviduct. Here it is inclosed in a membranous covering, called the chalazæ, and receives a coating of thick albumen. The function of the chalazæ is to keep the yolk suspended in the center of the egg. ”

“ The yolk of the egg is a still stronger or more nutritive fluid, which is drawn up into the bowels of the chick just at its exclusion from the shell, and serves it for nourishment for a day or two, till it is able to digest, and has learnt to choose the harder seeds or grains, which are to afford it sustenance. Nothing analogous to this yolk is found in the fetus of lactiferous animals, as the milk is another nutritive fluid ready prepared for the young progeny. ”

“ A full set of eggs is always desirable, if they can be obtained, but, as the old saying is, "A half-loaf is better than no bread." The contents may be removed by making a hole in the side of the egg with an egg drill, and sucking out the white and yolk with a glass blow-pipe, or by means of a little syringe with a bit of rubber tubing attached to the nozzle. ”

“ The fertile eggs should be opaque or clouded, and must be carefully replaced under the hen without shaking. If during incubation an egg should be broken, it must be removed, and the remainder taken out and cleansed in tepid water, otherwise the contents of the broken egg will cause the others to cling to the hen's fathers, and they too may become fractured. ”

“ When eggs which have been submitted to incubation permit light to shine through and show the yolk suspended in the upper half of the center as a clearly defined mass, which quickly reassumes its position in turning the egg with its long axis nearly horizontal, they are probably infertile or sterile. ”

“ Most eggs, together with their shells, are formed within the body of the egg-bearing animal, but this egg differs from the majority in this respect. It is true that the egg itself is formed as usual in the ovary, and passed through a tube known as the oviduct, but the shell or case is fabricated by the animal externally, and is slipped over the egg as it passes out of the oviduct and is about to be deposited. Eggs are very commonly laid in a nest, more or less elaborately constructed, and it is a rare thing for only one egg to be laid during the season by each individual. ”

“ This second membrane, enveloping the yolk of the germ of the chicken, is thickest at the two ends, having what may be termed bulgings, termed chalazes by anatomists; these bulgings of the second membrane pass quite through the white at the ends, and being thus, as it were, embedded in the white, they keep the inclosed yolk and germ somewhat in a fixed position, preventing them from rolling about within the egg when it is moved. ”

“ Nearly all the Platyhelminthes are HERMAPHRODITIC, and in nearly all there are, in addition to the ovaries producing ova, other glands attached to the female genital apparatus, namely, the vitellaria or yolk glands, which provide a substance termed yolk, which serves as nourishment for the embryo. The fully formed eggs have shells and are “compound,” i.e., composed of the egg or ovarian cell, which is surrounded by numerous yolk cells or their products of disintegration. ”

“ If you can buy it or are willing to make it raw milk yogurt containing lactobacillus bulgaris or acidophilus may be digested more readily, especially if it prepared from healthy cows or goats fed on unsprayed food, and served very fresh. Eggs should come from chickens that run around outside, eating weeds, and scratching bugs. The yokes of those eggs will be intense orange, not yellow. Few people these days have ever eaten a real egg. Surprisingly, for those of you who fear cholesterol, the healthy way to eat eggs is use just the raw yolk from fertile eggs. ”

“ An egg-cell consists of living protoplasm and a nucleus, a variable quantity of non-living food-yolk, and of certain enveloping and protective egg-membranes. The ova of Fishes differ principally in the amount and disposition of the food-yolk, in the character of the egg-membranes, and in the presence or absence of special perforations in the egg-membranes for the entrance of spermatozoa into the eggs. ”

“ Eggs of other individuals of the species, and even the eggs of Eumeces laticeps were accepted as part of the brood. Any of the experimental females would quickly retrieve one of her eggs moved a short distance outside the nest cavity. Even if the whole clutch of eggs were scattered about, the female would, over a period of hours, gather the eggs and return them to the nest cavity. This movement of the eggs is accomplished by rolling or pushing them in a loop of the body or tail, or, less frequently, by grasping an egg in the jaws, lifting it, and gently placing it in a new position. ”

“ The typical fish-egg is globular, more or less transparent, having a tough protective membrane, within which the yolk-laden egg proper lies. The yolk is present in sufficient amount to maintain the embryo until it can swim about and feed for itself. ”

“ The most philosophical mode of making the egg stand on its end and without disturbing the exterior shell is to alter the position of the yolk, which has a greater density than the white, and is situated about the centre. If the egg is now shaken so as to break the membrane enclosing the yolk, and thus allow it to sink to the bottom of the smaller end, the centre of gravity is lowered; there is a greater proportion of weight [Pg 36] concentrated in the small end, and the egg stands erect, as depicted at fig. ”

“ The frequent passage of large eggs is an accessory cause, and the egg becomes an important factor in the maintenance and aggravation of the inflammation. The mucosa becomes red, dry, infiltrated, thickened and friable, and the muscular coat increasingly paretic. The egg, becoming impacted, and subjected to constant pressure in the vain efforts at expulsion, hinders circulation and nutrition, and favors necrotic and ulcerative processes, and too often the fragile membranous walls yield, and the mass drops into the abdominal cavity. ”

“ The shape of eggs depends upon the position they have in the oötype during their formation. In young females an excess of cells—yolk cells especially—accumulates, distending not only the dorsal wall but a portion also of the short duct joining the oötype to the uterus. The result of this is that the axis of the oötype and egg is almost transverse to the body, and the posterior funnel-shaped portion of the oötype, instead of being terminal, has now a lateral or rather a ventral position, so that the spine which occupies this portion, instead of being terminal, is now lateral. ”

“ In such a case, the egg itself divides into a number of portions: two, four, eight, or even twelve and sixteen individuals being normally developed from every egg, in consequence of this singular process of segmentation of the yolk,—which takes place, indeed, in all eggs, but in those which produce but one individual is only a stage in the natural growth of the yolk during its transformation into a young embryo. ”

“ Most persons are familiar with the appearance of eggs, but in order that satisfactory results may be obtained in their selection, care, and cooking, it will be necessary to look into the details of their composition. As is well known, an egg consists of a porous shell lined with a fine, but tough, membrane that encloses the white and the yolk and serves to protect them. The yolk is divided from the white by a delicate membrane, which permits it to be separated from the white when an egg is carefully broken. ”

“ The porous nature of an egg shell is required to give air to the developing chick, but it is this characteristic that permits eggs to spoil as they grow old and are exposed to air, for through these minute pores, or openings, the water in the egg evaporates and air and bacteria enter. Of course, as the water evaporates and is replaced by air, the egg becomes lighter. Because of this fact, the freshness of eggs can be determined by placing them in water. When they are fresh, they will sink in cold water, but as they decompose they become lighter and will float. ”

“ The fat is accumulated in the yolk, often amounting to thirty per cent. Raw and lightly-boiled eggs are easy of digestion, but hard-boiled ones decidedly not so. An egg loses its freshness within a day or so. The shell is porous; and the always-feeding and destroying oxygen of the air quickly gains admission, causing a gradual decomposition. To preserve them, they must be coated with lard or gum, or packed in either salt or oats, points down. In this way they keep good a long time, and while hardly desirable to eat as boiled eggs, answer for many purposes in cooking. ”

“ The queen, on finding comb adapted to her needs, thrusts her head into a cell, apparently to ascertain if it is empty, and of the right depth and size for one of the two different kinds of eggs—those for workers, and those to become drones. Satisfied on these points, she withdraws her head, and, curving herself downwards, inserts her abdomen, and giving the lower part of her body a half-turn towards the thorax, she expels an egg from her oviduct, and then retires in search of other cells in which to make similar deposits. She rarely, and only by mistake, lays more than one egg in a cell. ”

“ What you would like to do, others, more skilful, have already done, not only opening the drawer but [49] breaking an egg each day so as to see how things are going. I told you that the germ of the bird is a round spot of dull white, the cicatricle, which by its mobility is always on top at the surface of the yolk, no matter what the position of the egg. ”

“ Table 5.—Measurements in Millimeters and Weights in Grams of Eggs in the Same Clutch at Different Stages During Their Incubation, Showing Gradual Increase in Size.
The extent of tolerance to immersion in water probably depends on the stage of development, the temperature, the oxygen content of the water and other factors. One egg was fully immersed for ten minutes on July 20, 1951, then returned to a container with damp soil in the laboratory, where it seemed to develop normally. On July 30 it was opened and found to have a living fetus, [56] which was a week short of hatching. ”

“ The extent to which the development of the embryo proceeds while it is still enclosed in the egg-membranes, and consequently the condition of the embryo when hatched, depends largely but not exclusively on the quantity of food-yolk which is present in the egg and available for the nutrition of the embryo during its earlier stages. ”

“ The period of yolk nutrition in the human is brief and probably variable. The minute size of the egg renders it impossible for it to furnish nutriment for any length of time, as is the case with the embryo of the fowl. From five to eight days after conception takes place, a membrane is formed around the ovum, called the chorion. Outside of this is still another membrane attaching itself to the womb. ”

“ Hens improperly fed lay eggs not only often unpalatable, but that are carriers of disease. The hen’s productive organs are so constructed that bacteria which she may take into her crop with impure food are passed into the egg. ”