. Bulletin of the British Museum (Natural History), Geology. FRUITING ORGANS FROM THE MORRISON FORMATION 151 reconstruction in Text-fig. 13 is not therefore intended as a portrait but serves to show that a Cycad-like structure is not impossible for the fragment which alone remains. In view of the scanty imperfect evidence the reference to Cycadales must be tentative only and no generic diagnosis can be based on this solitary fragment. CYCADOPHYTA ? Family ? Genus JENSENSISPERMUM nov. Diagnosis. Infructescence and fruit (if any) unknown. Seeds subovoid to subglobular, germinating by splitting a
. Bulletin of the British Museum (Natural History), Geology. FRUITING ORGANS FROM THE MORRISON FORMATION 151 reconstruction in Text-fig. 13 is not therefore intended as a portrait but serves to show that a Cycad-like structure is not impossible for the fragment which alone remains. In view of the scanty imperfect evidence the reference to Cycadales must be tentative only and no generic diagnosis can be based on this solitary fragment. CYCADOPHYTA ? Family ? Genus JENSENSISPERMUM nov. Diagnosis. Infructescence and fruit (if any) unknown. Seeds subovoid to subglobular, germinating by splitting at micropylar end. Integument probably pulpy. Funicle passing from hilum to chalaza through shallow hilar cavity. Hilar scar at inner end of cavity, large, gibbous, at right angles to longer axis of seed. Chalaza large, occupying approximately half of the seed connected at one end with hilar scar, penetrating into endosperm but later retracting and releasing it. Endo- sperm occupying other half of seed, turgid, at first hemispherical, later sometimes becoming conical by contraction, bearing a median navel-like embryo-scar. Type species. Jensensispermum redmondi gen. et sp. n. Jensensispermum redmondi gen. et sp. n. (Pis. 5-7, figs. 47-74 ; Text-figs. 14-28) Diagnosis. That of the genus. Syntypes. Brigham Young University, Utah, Nos. 22-30. Description. Seed. Subovoid when integument is preserved, pointed at micro- pyle (22, 23) which in some seeds is terminal on the longer axis opposite the hilum (22, 23) (PI. 5, figs. 47, 51 ; Text-fig. 17) and in others terminal on the shorter axis (24) ( ; Text-figs. 18, 19). The position varies with the shape of the seed. The variations may perhaps be related to situation on an unknown 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 (
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