Corpusculum

Corpusculum, a term, now unnecessary, formerly applied to the structure in the ovule of Gymnospermous plants which is now known to represent the archegonium (q.v.). There are generally two or more corpuscula embedded in the apex of the archisperm, which in this group fills the embryo-sac before fertilisation. Each consists of a large central cell filled with vacuolated protoplasm and a rosette of small neck-cells above it.