YOLK OF THE H E N ' S EGG
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FIG. 10. Diagrams illustrating gross changes in the oocyte during development. (After
Marza and Marza, 1935.)
1. The Nature of the 'Balbiani Body'
This specialized region lies to one side of the nucleus in young intrafollicular oocytes (up to about 0-2 mm). I t was first described by Balbiani
(1864) and has since been seen in many species of animals. There has
been considerable confusion as to the nature of the Balbiani body. Even
when discussion is restricted to birds, its composition is not entirely
clear. There are apparently several bodies that lie near the nucleus of
the young oocyte, namely, the centrosphere (d'Hollander, 1904; Loyez,
1906; van Durme, 1914; Brambell, 1926); the Golgi apparatus (van
Durme, 1914; Brambell, 1926; Ikeda, 1928; Das, 1931; Sluiter, 1940);