. Bulletin of the British Museum (Natural History), Geology. 182 MIDDLE JURASSIC OSTRACODA FROM NORTH LINCOLNSHIRE antennal scar is decidedly anteromedian in position. It may be either oval or kidney- shaped with a smaller scar in front. Possibly it is the fusion of these two scars which produces the single oval scar. A transitional stage as in type " A " has not been observed. A second feature of this particular type is the position of the adductor muscle scars. In the previous types these scars have formed a vertical or subvertical row on the inside of the valve, only rarely are th
. Bulletin of the British Museum (Natural History), Geology. 182 MIDDLE JURASSIC OSTRACODA FROM NORTH LINCOLNSHIRE antennal scar is decidedly anteromedian in position. It may be either oval or kidney- shaped with a smaller scar in front. Possibly it is the fusion of these two scars which produces the single oval scar. A transitional stage as in type " A " has not been observed. A second feature of this particular type is the position of the adductor muscle scars. In the previous types these scars have formed a vertical or subvertical row on the inside of the valve, only rarely are they situated in a slightly curved row. In the type under discussion here, the adductor scars are distinctly grouped cres- centically around the anteromedian antennal scar (Text-figs, n, 15).. Fig. 11. Type C muscle scar pattern. Praeschuleridea sp. nov. X 150 Type D In many Bajocian ostracods the antennal scar is U- or V-shaped with the opening of the scar directed dorsally. The antennal scar may be either anterodorsal or anteromedian in position with the adductor scars in a subvertical row behind, (Text-figs. 12, 13).. 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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