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Fig. 2.30 Schematic longitudinal sections of ovicells in: ( A ) Caberea
solida (endozooidal acleithral ovicell); ( B ) Bugulopsis monotrypa
(immersed cleithral ovicell) (communication pores of ooecia arrowed ).
Abbreviations: bc brood cavity, bcw brood-cavity wall, bw basal wall,
cr cryptocyst, dz distal zooid, ес ectooecium, en entooecium, fm
membranous frontal wall, m muscle strands of ooecial vesicle,
mz maternal zooid, oc ooecial coelom, of ovicell fl oor, op operculum,
sc sclerite of ooecial vesicle, tw transverse wall, v ooecial vesicle
2 Cheilostome Brood Chambers: Structure, Formation, Evolution