. Bulletin of the British Museum (Natural History). FARINGDON SPONGE GRAVEL BRYOZOA 93. Fig. 56 Hyporosopora larwoodi sp. nov., BM(NH) D55096, holotype; 56A, oblique view showing thick growth margin and absence of apertures on the frontal surface of the colony, x 29; 56B, growth margin, x 60. (Fig. 53A) in outline. Fan-shaped peripheral subcolonies may be developed from the main colony. In some colonies (Figs 55, 56), zooecia open only at the thick colony growing edge which reveals several tiers of zooecia. The pseudoporous frontal surface of the colony is devoid of apertures in thes
. Bulletin of the British Museum (Natural History). FARINGDON SPONGE GRAVEL BRYOZOA 93. Fig. 56 Hyporosopora larwoodi sp. nov., BM(NH) D55096, holotype; 56A, oblique view showing thick growth margin and absence of apertures on the frontal surface of the colony, x 29; 56B, growth margin, x 60. (Fig. 53A) in outline. Fan-shaped peripheral subcolonies may be developed from the main colony. In some colonies (Figs 55, 56), zooecia open only at the thick colony growing edge which reveals several tiers of zooecia. The pseudoporous frontal surface of the colony is devoid of apertures in these colonies and may be rugose with closely-spaced transverse wrinkles (Fig. 56A), with or without longitudinal ridges (Fig. 55) corresponding to the frontal walls of individual zooecia. In other colonies, zooecial apertures are present on the frontal surface, typically sparsely distributed in the depressed proximal part of the colony but closely spaced near the edge of the colony (Fig. 54). The distal fringe of the basal lamina extends up to 0-1 mm away from the budding zone. Autozooecia opening on frontal surfaces of colonies inter- sect the surface at an acute angle and have circular or transversely elongate apertures with thick rims. Blade- like mural spines have been observed within fractured autozooecia. The ancestrula has a protoecium about 0-21 mm in diameter (Fig. 53B). Gynozooecia (Figs 42, 52) have transversely elliptical frontal walls (broken in all available specimens) and terminal, transversely elongate ooeciopores smaller than the auto- zooecial apertures. Measurements. TAM, c. O-ll mm; FWW, c. 0-18 mm; GDL, 0-40 mm; GW, 100 mm; TOPM, 0 08 mm; LOPM, 0-05 mm. Remarks. This species is characterized by the small but thick colonies whose frontal surfaces either lack apertures or have apertures concentrated in a band close to the periphery of the colony. The zooecia make a shallow angle with the colony surface and it seems likely that slight variations in this angle det
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