. Bulletin of the British Museum (Natural History). TRIASSIC DEMOSPONGES IN KLIPSTEIN COLLECTION 49. Fig. 7 Cassianochaetetes sp. Cassian Fm., St Cassian. Specimen figured as Calamopora (?) gnemidium by Klipstein (1845: pi. 19, figs 16a, b), S10467. A, reproduction of Klipstein's fig. 16b. B, side view, x 5-9. C, top view showing astrorhizae, x 5-9. D, oblique longitudinal section, X 21. E, calicle walls, x 89. and shows growth Hnes. There is one astrorhizai system, radiating from the centre of the convex theca, consisting of shallow grooves which may bifurcate. The calicles are stro
. Bulletin of the British Museum (Natural History). TRIASSIC DEMOSPONGES IN KLIPSTEIN COLLECTION 49. Fig. 7 Cassianochaetetes sp. Cassian Fm., St Cassian. Specimen figured as Calamopora (?) gnemidium by Klipstein (1845: pi. 19, figs 16a, b), S10467. A, reproduction of Klipstein's fig. 16b. B, side view, x 5-9. C, top view showing astrorhizae, x 5-9. D, oblique longitudinal section, X 21. E, calicle walls, x 89. and shows growth Hnes. There is one astrorhizai system, radiating from the centre of the convex theca, consisting of shallow grooves which may bifurcate. The calicles are strongly bent and tabulae are very rare. Wall structure is elongate spherulitic. There are no spicules. Measurements (in mm) S10467 calicle diameter 0-19-0-28 wall thickness 0-03-0-06 Remarks. The general shape of the specimen most closely resembles Cassianochaetetes orbignyanus, but the calicles are much smaller, and the presence of an astrorhizai system is a further distinguishing feature. Although this probably repre- sents a new species, it would be unwise to propose a new name on the basis of the single available specimen. Some other Triassic calcified demosponges described as bryozoan genera The bryozoan literature includes several other examples of Triassic fossils which are more likely to be calcified demo- sponges. For example, Schiifer & Fois (1987) list eight so- called cerioporine cyclostomcs from the II. Triassic whose microstructures suggest that they may not be br\o/oans. The Klipstein Collection contains material which permits a de- tailed description and reinterpretation of one such supposed bryozoan genus. In two other cases, wc indicate possible synonymies and incorrect attributions. However, definite reassignments of many of these fossils must await detailed redescriptions of the type material. 1. Seelandia Bizzarini & Braga, 1978 Family CERATOPORELLIDAE Hartman & Gorcau. 1972 Genus ATROCHAETETES Cu\{ & Fischer, 1974 [ — Seelandia Bizzarini <
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