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Fig. 1.23 Oogenesis and extraembryonic nutrition during brooding in:
( A , C, D ) Reciprocus regalis ; ( B ) Urceolipora nana . ( A ) Ovaries,
spermatogenous tissue and nutrient-storage cells in adjoining zooids.
( B ) Early embryo in subimmersed ovicell with embryophore. ( C, D )
Parts of the late embryo in internal brood sacs with a placental analogue
( arrows indicate pale vacuoles and dark granules in embryophore cells).
Abbreviations: as ascus, bc brood cavity, bw basal wall, dz distal zooid,
е embryo, mz maternal zooid, nsc nutrient storage cells, ое ooecium, of
ovicell fl oor, op operculum, ov ovary, pl placental analogue (embryophore), st spermatogenous tissue, tw transverse wall, v ooecial vesicle.
Scale bars: A – C , 20 μm
Figures
Fig. 1.23 Oogenesis and extraembryonic nutrition during brooding in:
( A , C, D ) Reciprocus regalis ; ( B ) Urceolipora nana . ( A ) Ovaries,
spermatogenous tissue and nutrient-storage cells in adjoining zooids.
( B ) Early embryo in subimmersed ovicell with embryophore. ( C, D )
Parts of the late embryo in internal brood sacs with a placental analogue
( arrows indicate pale vacuoles and dark granules in embryophore cells).
Abbreviations: as ascus, bc brood cavity, bw basal wall, dz distal zooid,
е embryo, mz maternal zooid, nsc nutrient storage cells, ое ooecium, of
ovicell fl oor, op operculum, ov ovary, pl placental analogue (embryophore), st spermatogenous tissue, tw transverse wall, v ooecial vesicle.
Scale bars: A – C , 20 μm
Figures