. Animal physiology. Physiology, Comparative. 580 STRUCTURE OF THE BIRD S EGG. own substance is scarcely distinguishable. ISTot only thousands but tens of thousands of eggs are often produced by a single individual, their aggregate forming what is known as the "hard roe;" whilst the "soft roe" or "milt" is the corre- sponding mass of sperm-cells produced by the male. 755. After the ovuin of the Bird has quitted the ovarium, and is passing through the oviduct towards its outlet, it receives layer after layer of albumen poured out in a viscid condition from the lini
. Animal physiology. Physiology, Comparative. 580 STRUCTURE OF THE BIRD S EGG. own substance is scarcely distinguishable. ISTot only thousands but tens of thousands of eggs are often produced by a single individual, their aggregate forming what is known as the "hard roe;" whilst the "soft roe" or "milt" is the corre- sponding mass of sperm-cells produced by the male. 755. After the ovuin of the Bird has quitted the ovarium, and is passing through the oviduct towards its outlet, it receives layer after layer of albumen poured out in a viscid condition from the lining membrane of the oviduct, forming the "white" of the egg (fig. 315, g); and this is inclosed in. Fig. 315.—Section of Fowl's Egg : a, cicatricula; b, yolk-bag; c, membrane lining shell; d, attachment of chalazae; e, chalazae; /, air-space ; g, albumen. a double membrane composed of a network of fibres, which is fc)rmed by the consoliclation of a jjlastic exudation (§ 391), poured out after the albuminous exudation has been com- pleted. The outer layer of this membrane is consolidated by the deposit of calcareous particles in the interspaces of its fibrous matting, so as to form the " shell" of the egg; an arrangement that gives the necessary protection, without cut- ting-off the contents of the shell from that communication with the atmosphere which is requisite for the development of the embryo. The inner layer, which forms a lining to the shell, separates into two lamiiiDC at the large end of the egg ; and, inclosed between these, there is a bubble of air (f), which serves to give the young bird, just before it is hatched, the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Carpenter, William Benjamin, 1813-1885. London : H. G. Bohn
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Keywords: ., bookauthorcarpente, bookcentury1800, bookdecade1850, bookyear1859
