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In cestodes and trematodes, a common chamber receiving vitelline (yolk) material from the two vitelline ducts; the yolk material then passes into the ootype to surround the ovum with nutritive vitelline granules that are enclosed by a characteristically formed eggshell.
Synonym(s): vitelline reservoir
n. pl. vitellar·iums or vitellar·ia (-ē-ə)
A group of glands in flatworms and certain other invertebrates that secrete yolk.
a gland which forms yolk.