A—Latrunculia sp. (after Hinde). Cainozoic. Deep Lead, Norseman, W.A.
B—Geodia sp. (after Hinde). Cainozoic. Deep Lead, Norseman, W.A.
C—Ecionema newberyi. McCoy sp. Cainozoic. Boggy Creek, Gippsland, Vict.
D—Plectroninia halli, Hinde. Cainozoic (Janjukian). Moorabool, Vict.
E—Tretocalia pezica, Hinde. Cainozoic. Flinders, Vict.
A—Cyathophyllum approximans, Chapm. Silurian (Yer.). Gippsland, Vict.
B—Favosites grandipora, Eth. fil. Silurian (Yer.). Lilydale, Vict.
C—Favosites grandipora, vertical section. Ditto.
D—F. grandipora, transverse section. Ditto.
E—Pleurodictyum megastomum, Dun. Lilydale, Vict.
F—Halysites peristephesicus, Eth. fil. Silurian. N.S. Wales.
G—Heliolites interstincta, Wahl sp Vict. (transv. sect). Silurian..
In the Cainozoic beds of southern Australia Sponges with calcareous skeletons are not at all uncommon. The majority of these belong to the Lithonine section of the Calcispongiae, in which the spicules are regular, and not fixed together. Living examples of these sponges, closely related to the fossils, have been dredged from the Japanese Sea. The fossils are found mainly in the Janjukian, at Curlewis, in the Moorabool River limestones, and in the polyzoal rock of Flinders, all in Victoria. They belong to the genera Bactronella, Plectroninia and Tretocalia (Fig. 68, D and E). Some diminutive forms also occur in the older series, the Balcombian, at Mornington, namely, Bactronella parvula. At Boggy Creek, near Sale, in Victoria, a Tetractinellid Sponge, Ecionema newberyi, is found in the Janjukian marls; spicules of this form have also been noted from the clays of the Altona Bay coal-shaft ([Fig. 68 C]).