. Animal physiology. Physiology, Comparative. DEVELOPMENT OF OVA OF BIRD. 579 to that of tlie parent, tlian we see in any other animals. The appearance of the ovary of the Fowl in process of laying is shown in fig. 314 ; its surface is rendered uneven or knobby. Fig, 314.—Ovary of the Fowl, with ova in various stages of development: a, mature ovum within its calj x, which is about to rupture along the non-vascular streak bb; c c, less advanced ova ; d, a calyx from which tlie ovum has escaped ; e, still younger ova. by the protrusion of the ova in various stages of enlargement, those which are
. Animal physiology. Physiology, Comparative. DEVELOPMENT OF OVA OF BIRD. 579 to that of tlie parent, tlian we see in any other animals. The appearance of the ovary of the Fowl in process of laying is shown in fig. 314 ; its surface is rendered uneven or knobby. Fig, 314.—Ovary of the Fowl, with ova in various stages of development: a, mature ovum within its calj x, which is about to rupture along the non-vascular streak bb; c c, less advanced ova ; d, a calyx from which tlie ovum has escaped ; e, still younger ova. by the protrusion of the ova in various stages of enlargement, those which are most mature (a, c) forming pear-shaped projections which only hang-on by a narrow stalk ; but each ovnm is still included within an extension of the fibrous sub- stance of the ovary (fig. 302), termed the cah/x, through which blood-vessels are conveyed over its surface; and when the ovum escapes by the rupture of this, along a line (b) from which the vessels have previously retreated, the calyx remains as an open cup (d). The ovarium of such Mammals as pro- duce several young at once, presents a corresponding appear- ance as each set of ova is approaching maturity ; save that, as the mass of yolk is comparatively small (no "food-yolk" being provided), the ova do not project so much from its surface. In Fishes, on the other liand, we find an enormous number of ova produced at once ; the whole ovarium, when they are approaching maturity, being so crowded witV them that its pp 2. 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
