“…With kind permission by La Recherche. Bannister, Bannister, and Anastasi, 1976 The hexagon center is generally devoid of subunits and was constituted by a hole of about 7-8 nm diameter; however, some annelid EHbs were shown to possess a central subunit, such as Oenone fulgida (Van Bruggen and Weber, 1974), Nepthys hombergii (Wells and Dales, 1976), Nepthys incisa (Wells and Dales, 1976;Messerschmidt et al, 1983;Vinogradov and Kapp, 1983), Ophelia bicornis Mezzasalma et al, 1985;Cejka et al, 1991Cejka et al, , 1992, Maoridrilus montanus (Ellerton et al, 1987), Glossoscolex paulistus (El Idrissi Slitine, Torriani, and Vachette, 1990), Eophila tellinii (Cejka et al, 1989), Euzonus mucronata (Terwilliger et al, 1977b), and Arenicola marina (Zal et al, 1997a(Zal et al, , 1997b (Figure 16.3). The existence of a central subunit suggested that this was similar or equivalent to another one-twelfth of the native molecule, although to date no central subunit has been isolated and/or characterized.…”