. Bulletin of the British Museum (Natural History), Geology. . Fig. 15. Gonyaulacysta sp. G. Tabulation and archaeopyle formation (plate 3" is missing). Left, in ventral view; right, in dorsal view. Specimen BM(NH) slide (i). X Dimensions: Figured specimen: overall length 75fx, breadth 45[a, apical horn length I0[x, breadth of the cingulum 5jjl. Remarks : This single specimen differs from the described species of Gonyaulacysta in its general shape and distinctive sutural crests. The tabulation and perforate crests are similar to those in G. perforans, but in the other morp
. Bulletin of the British Museum (Natural History), Geology. . Fig. 15. Gonyaulacysta sp. G. Tabulation and archaeopyle formation (plate 3" is missing). Left, in ventral view; right, in dorsal view. Specimen BM(NH) slide (i). X Dimensions: Figured specimen: overall length 75fx, breadth 45[a, apical horn length I0[x, breadth of the cingulum 5jjl. Remarks : This single specimen differs from the described species of Gonyaulacysta in its general shape and distinctive sutural crests. The tabulation and perforate crests are similar to those in G. perforans, but in the other morphological characters those species are dissimilar. Gonyaulacysta sp. H Plate 13, figure i, text-figure 16 Description : Cyst subpolygonal to ovoidal, with a strong apical horn of moderate length. The cyst wall is rather thick and composed of two layers, the periphragm alone forming the horn; the surface of the periphragm is densely and finely granular Tabulation 4-?5', la, 6", 6c, 5'", op, ?ipv, 1"". The sutures are indicated by low ridges, from which arise small prominences, too blunt and short to be called spines. The number of apical plates is doubtful only because a small circular plate appears to cap the horn: four other plates can clearly be seen, plate i' being unusually large and broad. Plate 6" of the precingular series is reduced to accommodate an obliquely positioned anterior intercalary plate: plate 3" is lost in archaeopyle 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(NH)
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