. Bulletin of the British Museum (Natural History), Geology. 208 KIMMERIDGIAN DINOFLAGELLATES & ACRITARCHS (The antapical end of the sulcus and the plate boundaries near to the antapex were not very clear because of bad preservation of this part of the cyst.) The first post- cingular plate, i'", is narrow, elongate and small. Plate 4'" appears the largest of the post-cingular plates. No archaeopyle was observed in this specimen. Figured specimen: slide , Sample WB 16, from Geological Survey Borehole, Warlingham, Surrey, at 2510 ft depth. Middle Kimmeridgian (Sci
. Bulletin of the British Museum (Natural History), Geology. 208 KIMMERIDGIAN DINOFLAGELLATES & ACRITARCHS (The antapical end of the sulcus and the plate boundaries near to the antapex were not very clear because of bad preservation of this part of the cyst.) The first post- cingular plate, i'", is narrow, elongate and small. Plate 4'" appears the largest of the post-cingular plates. No archaeopyle was observed in this specimen. Figured specimen: slide , Sample WB 16, from Geological Survey Borehole, Warlingham, Surrey, at 2510 ft depth. Middle Kimmeridgian (Scitulus Zone). Dimensions : Overall length yyy., breadth 6o(jl, apical horn length 8\i. Remarks: Only one specimen has so far been observed. It is distinguished from all previously described species in its overall morphological features; it is possibly a new species, but further specimens are needed to decide this. Gonyaulacysta sp. D Plate 6, figures 4-5; text-figure 12 Description: A specimen with an almost spherical cyst and short, blunt, tapering apical horn. The shell wall is composed of two layers, periphragm and endophragm, which are of the same thickness; the periphragm is coarsely granular. The apical horn is formed of both shell layers. Tabulation: 4', la, 6", 6c, 6'", ip and I"". Plate i' is elongate and occupies the anterior prolongation of the sulcus. Plates 2' and 3' are large; plate 4' is slightly reduced to accommodate the anterior intercalary plate, la. Four apical plates together make up the apical horn. Plate la is quite large; because of this, plate 6" is reduced. The other precingular plates are of more or less similar shape and size. The cingulum is of moderate breath,. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original British Museum (Natural History). London : BM(N
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