. Bulletin of the British Museum (Natural History), Geology. SYSTEMATICS OF MELICERITITID CYCLOSTOME BRYOZOANS 55. Figs 146, 147 Reptomultelea sarthacensis (d'Orbigny, 1853), gonozooids, VH 10432 Lower Cenomanian, Mulheim-Broich, Westfalia, Germany; 146, gonozooid with broken frontal wall; note fouling tubuliporine cyclostome which has become enveloped proximally by an overgrowth of melicerititid kenozooids, x 60; 147, two coalescent gonozooids sharing a single ooeciopore, x 70. layer about 0-23 mm thick, often growing free of the substra- tum and with a transversely folded basal lamina. Ances
. Bulletin of the British Museum (Natural History), Geology. SYSTEMATICS OF MELICERITITID CYCLOSTOME BRYOZOANS 55. Figs 146, 147 Reptomultelea sarthacensis (d'Orbigny, 1853), gonozooids, VH 10432 Lower Cenomanian, Mulheim-Broich, Westfalia, Germany; 146, gonozooid with broken frontal wall; note fouling tubuliporine cyclostome which has become enveloped proximally by an overgrowth of melicerititid kenozooids, x 60; 147, two coalescent gonozooids sharing a single ooeciopore, x 70. layer about 0-23 mm thick, often growing free of the substra- tum and with a transversely folded basal lamina. Ancestrula not observed. Overgrowths (Figs 148-149) presumed to origi- nate by intrazooecial fission; pseudoancestrulae with depressed apertures, small (ca 0-08-0-09 mm), more or less equidimensional and less pointed than apertures of autozoo- ids from zone of astogenetic repetition. Organization fixed- walled. Zooids arranged in irregular quincunx. Autozooids (Figs 150, 152) small, frontally elongate, about twice as long as wide, subhexagonal with a moderately pointed distal end; frontal wall generally occupying more than half of frontal surface, pseudopores subcircular; bound- ary wall poorly defined, subdued. Aperture of small size, slightly elongate, about 1-1-1-2 x longer than wide, widest between the hinge line and mid-length, slightly arched to rounded distally; apertural rim well-developed distally where it may be prolonged into a pointed projection; hinge line bowed, detailed structure unclear; apertural shelf very nar- row or absent. Operculum (Fig. 151) sometimes preserved in-situ, flat centrally but with slightly convex sides, possessing about 20 slit-like pseudopores arranged in a crescent parallel to the disto-lateral edge; inner surface with narrow sclerites forming a low arch across the distal edge of the operculum where they are joined. Terminal diaphragms and intramural buds not observed. Eleozooids (Figs 148, 150, 152-153) numerous, scattered; small, frontally elo
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