. Bulletin of the British Museum (Natural History), Geology. FROM GREAT BRITAIN AND FRANCE 265. Fig. 14. Gonyaulacysta sp. B. Tabulation. Left, ventral view ; right, dorsal view. xc. 950. placed below plate 1" '. A crescent-shaped plate (ipv) separates the single antapical plate 1" " from the sulcus. Plate 1" " is characteristically surrounded by long (nearly three times longer than the sutural spines), thin, simple spines. No archaeopyle was seen. Figured specimen. BM(NH) slide ¥.53965(2). Clay from Argiles de Moulin Wibert (20 ft. below the top) south side of Cap de
. Bulletin of the British Museum (Natural History), Geology. FROM GREAT BRITAIN AND FRANCE 265. Fig. 14. Gonyaulacysta sp. B. Tabulation. Left, ventral view ; right, dorsal view. xc. 950. placed below plate 1" '. A crescent-shaped plate (ipv) separates the single antapical plate 1" " from the sulcus. Plate 1" " is characteristically surrounded by long (nearly three times longer than the sutural spines), thin, simple spines. No archaeopyle was seen. Figured specimen. BM(NH) slide ¥.53965(2). Clay from Argiles de Moulin Wibert (20 ft. below the top) south side of Cap de La Creche, Boulonnais (CC 447). Dimensions. Figured specimen : overall length y8 /n, breadth 50 /x ; horn length 8 (i ; length of the sutural processes 3-5 fi, antapical processes 8 yu. ; breadth of the cingulum 3-5 it. The second specimen could not be measured. Remarks. Only two specimens were encountered, one of them badly preserved but the other good enough for study. With their long processes around the antapex, these specimens are different from all described species of Gonyaulacysta ; this is probably a new species but, for fuller knowledge, more specimens must be examined. Gonyaulacysta sp. C (PI. 4, figs. 10, 11 ; Text-fig. 15) Description. This is an infrequent species. All the three specimens encoun- tered are somewhat crushed, folded or covered by debris ; the one figured was the best oriented for study. The surface is densely granular ; because of the granulation and bad orientation, it was difficult to distinguish the tabulation. The thick-walled theca is almost spherical, with a moderately long apical horn. Tabulation : 4', ia, 6", 6-yc, 7" ', ip, ipv, 1" ". Plate 1' occupies the anterior prolongation of the sulcus. Plates 2' and 3' are small ; the position of the boundary between them was not confirmed. Plate 4' is almost as large as plate 1'. The single anterior intercalary plate is small, placed between the plates 4' and 6". The pre-.
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