. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. OVUM. 65 D. D. Egg from the lower part of the glandular oviiluct near the isthmus, when the deposit of albu- men is complete; the spiral arrangement of the albumen made manifest by slight coagulation. attached to the opposite ends or poles of the yolk by means of a membrane which looks ex- actly like a continuation of the twisted part of these bodies opening or expanded over the surface of the vitelline membrane. These bodies attracted considerable notice from the earlier observers of the structure of the egg, and have h
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. OVUM. 65 D. D. Egg from the lower part of the glandular oviiluct near the isthmus, when the deposit of albu- men is complete; the spiral arrangement of the albumen made manifest by slight coagulation. attached to the opposite ends or poles of the yolk by means of a membrane which looks ex- actly like a continuation of the twisted part of these bodies opening or expanded over the surface of the vitelline membrane. These bodies attracted considerable notice from the earlier observers of the structure of the egg, and have had various uses attributed to them ; but, if we may judge from the varieties they are subject to in the fowl and other birds, and their absence in the ova of scaly reptiles (otherwise very similar to those of birds), it would appear that they are only of secondary importance. One of the chalazse is directed towards the larger, and the other to the smaller end of the egg, and the latter usually adheres with some firmness to the inside of the shell-membrane, while that of the large end floats more freely. In this manner the yolk moves more freely at the large than at the small end of the egg. The spiral twist is in opposite direc- tions in the two chalazae; a circumstance depending on the manner of their production, by the gradual deposit of albumen and the spiral motion of the yolk during its descent in the oviduct. The membrane which pro- ceeds from the cbalazas over the surface of the yolk has been called chalaziferous; and the funnel-shaped dilatation of the chalazae where they join the membrane, has been sup- posed to be the opening of a tube passing through these bodies, and serving as a conduit from the white to the yolk ; but entirely without reason. The chalaziferous membrane and innermost twisted part of the chalazoe are, in fact, nothing more than the first- deposited and densest parts of the albumen ; nor is any importance to be attributed to a curved line or fold of
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