Seminal vesicles were fi xed for 3h in a solution of 2.5% glutaraldehyde, in 0.1 M
cacodylate buffer, pH 7.2, 0.2% picric acid, 3% sucrose and
5 mM CaCl2. They were post fi xed in 1% osmium tetroxide
in the same buffer and then dehydrated in acetone and
embedded in Epon 812. Ultrathin sections were stained with
uranyl acetate and lead citrate and observed with the Zeiss
LEO 906 transmission electron microscope.