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FIG. 8. Regeneration of the copulatory apparatus of Polycelis nigra. a: condensation
of neoblasts; b : stage 1, hollowing out of the genital atria; c : stage 2, appearance of the
penis, hollowing out of the oviduct; d: stage 3, differentiation of the penis and of the
musculo-glandular organs, hollowing out of the copulatory pouch. AC: common genital
atrium; AM: male genital atrium; BC: copulatory pouch; EC: formation of the common
genital atrium; EM: formation of the male genital atrium; OMg: musculo-glandular
organ; OV: oviduct; P : penis.
A.M. 2