. Bulletin of the British Museum (Natural History), Geology. FROM ENGLAND, SCOTLAND AND FRANCE 207 Dimensions: Overall length 4811, breadth 45[x, horn length ^y., sutures 3-5;ji, high. Remarks: In its general morphological features and sutural characteristics, this species may be distinguished from all previously described species of Gonyaiilacysta. The shape of the shell and crests is most comparable to G. serrata Cookson & Eisenack (1958) suggesting a relationship between the two species, but the form of the apical horn is different; since a tabulation could not be determined for G. serr
. Bulletin of the British Museum (Natural History), Geology. FROM ENGLAND, SCOTLAND AND FRANCE 207 Dimensions: Overall length 4811, breadth 45[x, horn length ^y., sutures 3-5;ji, high. Remarks: In its general morphological features and sutural characteristics, this species may be distinguished from all previously described species of Gonyaiilacysta. The shape of the shell and crests is most comparable to G. serrata Cookson & Eisenack (1958) suggesting a relationship between the two species, but the form of the apical horn is different; since a tabulation could not be determined for G. serrata, a detailed comparison of these two species is impossible. Gonyaulacysta sp. C Plate 6, figures 1-2, text-figure 11 Description : The cyst is subspherical, bearing a short, tapering apical horn. The thickness of the wall is uneven because of irregularly distributed granules. The sutural crests are in the form of low ridges giving rise occasionally to delicate mem- branes: they indicate a reflected tabulation of 4', la, 6", 6c, 6"', ?ipv, i"". Four apical plates together form the horn; plate i' is elongate in shape. The precingular plates, except plate 6", are of almost uniform shape and size; plate 6" is reduced to accommodate the intercalary plate la. Six cingular plates make up the slightly helicoid, laevorotatory cingulum: plate 6c is very small, the others are relatively large. The ends of the cingulum are widely separated by a very broad sulcus, which further widens in its posterior Fig. II. Gonyaulacysta sp. C. Tabulation: left, in ventral view; right, in dorsal view. Specimen slide PK 118. x 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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