. Bulletin of the British Museum (Natural History), Geology. A $ %$?:. ftill Fig. 71 £7<?a mackinneyi sp. nov., VH 10474, holotype. Lower Cenomanian, Mulheim/Ruhr, Westfalia, Germany; gonozooid with broken frontal wall exposing atrial ring, x 48. Name. With reference to the resemblance to Elea hexagona. Description. Colony bifoliate with branches (Fig. 79) bifur- cating, strap-like, narrow, about 1-3-2-3 mm wide. Autozoo- ids generally arranged in approximate quincunx; organization fixed-walled. Colony base not observed. Overgrowth present in ZMC M54, consisting of kenozooids spreading betw
. Bulletin of the British Museum (Natural History), Geology. A $ %$?:. ftill Fig. 71 £7<?a mackinneyi sp. nov., VH 10474, holotype. Lower Cenomanian, Mulheim/Ruhr, Westfalia, Germany; gonozooid with broken frontal wall exposing atrial ring, x 48. Name. With reference to the resemblance to Elea hexagona. Description. Colony bifoliate with branches (Fig. 79) bifur- cating, strap-like, narrow, about 1-3-2-3 mm wide. Autozoo- ids generally arranged in approximate quincunx; organization fixed-walled. Colony base not observed. Overgrowth present in ZMC M54, consisting of kenozooids spreading between apertures of underlying autozooids, possibly free-walled (Fig. 79). Autozooids (Figs 80, 81) medium-sized; frontal surface usually hexagonal, elongate, about twice as long as wide; frontal wall occupying about half of frontal surface, flat with circular pseudopores; zooecial boundaries raised. Apertures (Fig. 83) small, longitudinally elongate, on average 1-1—1-2 x longer than wide, attaining maximum width between hinge line and mid-length, rounded distally; aper- tural shelf narrow; apertural rim well-developed; hinge line with a subdued median bar. Opercula (Fig. 82) often pre- served in-situ, surface convex, sometimes with a flattened median area close to the hinge line, pseudopores not visible in studied material. Terminal diaphragms not observed. Intramurally budded autozooids may be present, their aper- tures typically shorter and more rounded than normal auto- zooids. Eleozooids (Figs 84-85) common, especially at branch margins and in bifurcations, about 3-4 x longer than wide, frontally slightly wider but appreciably longer than autozoo- ids. Aperture elongate, about 2-3 x longer than wide, widest at the hinge line and tapering to a long narrow rostrum with a rounded end. Opercula (Fig. 84) observed in-situ, surface convex. Intramurally budded eleozooids (Fig. 81) present. Kenozooids sometimes present in branch bifurcations. Gonozooids (Fig. 86) with a short para
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