. Bulletin of the British Museum (Natural History). FARINGDON SPONGE GRAVEL BRYOZOA 107. Fig. 89 Melkeritites dendroidea (Keeping), BM(NH) D52153, broken gynozooecium, x 69. pseudoporous to non-pseudoporous, occasionally with a central depression and pore. Opercula are frequently found in situ\ worn examples have 10-12 pits arranged in a crescent parallel to the lateral and distal edges of the operculum. The inner surfaces of dissected opercula appear to lack distinct sclcrites but have a raised marginal shelf. Eleozooecia have not been observed in Faringdon speci- mens; however, a s
. Bulletin of the British Museum (Natural History). FARINGDON SPONGE GRAVEL BRYOZOA 107. Fig. 89 Melkeritites dendroidea (Keeping), BM(NH) D52153, broken gynozooecium, x 69. pseudoporous to non-pseudoporous, occasionally with a central depression and pore. Opercula are frequently found in situ\ worn examples have 10-12 pits arranged in a crescent parallel to the lateral and distal edges of the operculum. The inner surfaces of dissected opercula appear to lack distinct sclcrites but have a raised marginal shelf. Eleozooecia have not been observed in Faringdon speci- mens; however, a specimen from the Aptian Bargate Stone of Kent possesses eleozooecia with apertures of a similar shape to the autozooecia but about twice the size. Gynozooecia are moderately common. The bulbous distal part of the frontal wall has a longitudinally elliptical to pear- shaped outline (Figs 85B, 89), often with a parallel-sided initial portion leading from the hemi-elliptical parental aper- ture. Autozooecia and kenozooecia bordering the gynozo- oecium are often raised. Intcrzooecial walls of occluded autozooecia are prominent on the floor of abraded gynozooecia (Fig. 85B), but an atrial ring has not been observed. The ooeciopore, situated a little distal of the bulbous part of the gynozooecium, is transversely elliptical (Fig. 85C); in one example it is apparently occluded by a diaphragm. Measurements (autozooecial dimensions from 10 determi- nations of zooecia in one colony; gynozooecial dimensions from measurements of 6 gynozooecia). FWL, 0-32-0-39 mm; FWW, 0-18-0-23 mm; LAM, 0-08-fl-09 mm; TAM, 0-08-0-09 mm; GTL, 111-1-58 mm; GDL, 0-92-1-35 mm; GW, 0-75- 0-93 mm; LOPM, 0-05 mm; TOPM, 0-08-0-09 mm. Remarks. Meliceritites dendroidea is a very common species at Faringdon and can be distinguished from the other meli- cerititids by the small size of the apertures and the narrow diameter of the branches. The species is usually incorrectly cited as Meliceritites semiclausa (Michelin),
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