. Bulletin of the British Museum (Natural History), Geology. . Figs. 37-42. Carpolithus radiatus sp. n. Fig. 37. Base of a seed showing central stalk and radial marginal furrows. Fig. 38. Side, showing slight concavity of apex, sometimes present, and rounded margin. Fig. 39. Apex, radial furrows again shown diverging from central micropyle (?). Fig. 40. Median longitudinally sectioned specimen with central longitudinal canal and fibres and shallow radial cavity on right. Fig. 41. Apicolateral view of seed with internal cast (= endosperm) exposed by abrasion of integument. Central depression an
. Bulletin of the British Museum (Natural History), Geology. . Figs. 37-42. Carpolithus radiatus sp. n. Fig. 37. Base of a seed showing central stalk and radial marginal furrows. Fig. 38. Side, showing slight concavity of apex, sometimes present, and rounded margin. Fig. 39. Apex, radial furrows again shown diverging from central micropyle (?). Fig. 40. Median longitudinally sectioned specimen with central longitudinal canal and fibres and shallow radial cavity on right. Fig. 41. Apicolateral view of seed with internal cast (= endosperm) exposed by abrasion of integument. Central depression and embryo scar and channel between the latter and the margin are seen. On left is a second young seed (or ? shoot in early stages). Fig. 42. Apex of two contiguous seeds growing, almost fused, on the same stalk. Stippling indicates adherent matrix on their surfaces. have lost the stalk and lower part of the integument, presumably destroyed before fossilization. In such instances a transversely rugose lower surface of the seed cast is exposed (PI. 10, fig. 120). It recalls the tissues of the chalazal region in Jensensi- spermum (p. 156) but in the present instance the region is situated on the lower surface of the seed above the erect stalk (raising the question whether the chalaza in Jen- sensispermum should be placed below rather than above). The rugosities tend to diverge from a point near the circumference. In 63, there is a marginal truncation at this point, emphasized by a raised rim. In 58 scar and rim are not clearly defined but the rugosities with marginal divergence are particularly clear (PI. 10, fig. 120) as is the radial arrangement of the upper surface (PI. 10, fig. 119). It seems probable that the point of divergence and truncation indicate the hilar scar at one side of the chalazal region as in Jensensispermum. The specimen which best shows the curved appearance and apical depression of the endosperm (53) also dis-. Please note that these images are extrac
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