. Bulletin of the Natural Histort Museum. Geology series. Figs 63-65 Dyscritella miliaria (Nicholson, 1881); 63, Upper part of the Glencar Limestone (Visean, Asbian), Sillees River, County Fermanagh; BELUM K3442; 63a, large zoarial fragments showing ramose growth-form and large circular autozooecial apertures surrounded by irregularly-placed exilazooecia. xl;63b. detail of 63a, x 15; 63c, cross-section showing autozooecial chambers with thickened exozonal walls, x50; 63d, detail of 63c, showing exilazooecium developed in exozone between adjacent autozooecial apertures, xl20; 64-65, Carbonifero
. Bulletin of the Natural Histort Museum. Geology series. Figs 63-65 Dyscritella miliaria (Nicholson, 1881); 63, Upper part of the Glencar Limestone (Visean, Asbian), Sillees River, County Fermanagh; BELUM K3442; 63a, large zoarial fragments showing ramose growth-form and large circular autozooecial apertures surrounded by irregularly-placed exilazooecia. xl;63b. detail of 63a, x 15; 63c, cross-section showing autozooecial chambers with thickened exozonal walls, x50; 63d, detail of 63c, showing exilazooecium developed in exozone between adjacent autozooecial apertures, xl20; 64-65, Carboniferous shales (probably Redesdale Ironstone Shale (Asbian). Lower Limestone Group), Redesdale, Northumberland; 64, (lectotype), ramose branching zoarial fragment with crowded arrangement of autozooecial apertures surrounded by much smaller circular or irregularly-shaped exilazooecial apertures, x5; 65, GSM 1967, (paralectotype), tangential section showing oval autozooecial apertures surrounded by numerous exilazooecia, xl5. rapidly at the endozone/exozone boundary, and wall thickness re- mains constant (mean thickness ) throughout most of the texozone. Thin basal diaphragms are infrequently developed in the endozone, whereas very thin diaphragms are occasionally devel- oped in the exozone. , Autozooecial apertures are of moderate size, circular in shape, .and are closely packed, approximately their own diameter apart. Interapertural areas are irregular in width. Exilazooecia are very abundant between autozooecia and vary greatly in shape and size, rhey are usually circular to oval, but in interapertural angles small jentagonal forms occur ( in diameter). Frequently, one f)rtwo exilazooecia are located between autozooecia. Exilazooecia originate within the exozone where they form short, narrow tubes. Vlaculae, in diameter, occur occasionally and comprise ;lusters of exilazooecia. I Acanthostyles are abundant in interapertural walls. Relatively
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