. Bulletin of the British Museum (Natural History), Geology. FRUITING ORGANS FROM THE MORRISON FORMATION 153 21, 23, 25) from whose margin striations due to fine lines of contraction, but also fine nerves diverge onto its surface. The nerves can be detected for a short distance only (29) (PI. 7, fig. 68) and are best exposed when most of the chalazal area is missing. The endosperm evidently arises from and is firmly attached to the chalazal area which abuts upon the gibbous part of the hilar scar (PI. 6, fig. 58 ; Text-fig. 23). In the less abraded seeds the area may be very thick (35). It com
. Bulletin of the British Museum (Natural History), Geology. FRUITING ORGANS FROM THE MORRISON FORMATION 153 21, 23, 25) from whose margin striations due to fine lines of contraction, but also fine nerves diverge onto its surface. The nerves can be detected for a short distance only (29) (PI. 7, fig. 68) and are best exposed when most of the chalazal area is missing. The endosperm evidently arises from and is firmly attached to the chalazal area which abuts upon the gibbous part of the hilar scar (PI. 6, fig. 58 ; Text-fig. 23). In the less abraded seeds the area may be very thick (35). It commonly appears to overlap onto the endosperm and partly embrace it. It lies, of course, opposite to the micropyle. When present, the cast of the hilar-cavity slightly overlaps both halves of the seed (Text-figs. 17, 19, 20). In a few better preserved specimens the surface ch ch. Figs. 17-19. Jensensispermum redmondi gen. et sp. n. Fig. 17. Seed as in Text-fig. 14 with micropyle opposite hilum depicted with pulpy integument removed on near side so as to expose internal cast. In this seed endosperm has become conical with embryo at point of cone. The chalazal area is somewhat shrunk and retracted. Integument reconstructed. Fig. 18. Seed with downward directed micropyle. Epidermis abraded exposing shredded dried pulpy integument. Fig. 19. Seed of similar shape to 18 but with pulp removed on near side as in 17. The endosperm is smoothly rounded and chalazal area unshrunk (integument reconstructed), cav, cavity at hilar end represented by a calcite cast through which funicle passes to inner side of hilar scar and chalazal area, ch. e, embryo scar in endosperm, en. h, hilar region ; m, micropyle ; sp, plane of splitting ; t, pulpy integument. of the chalaza which lay in contact with the integument is smoothly finished and traversed by distinct separate longitudinal nerves arising at the edge of the hilar scar or from beneath the cast of the hilar cavity (28, ). The nerves somet
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