. Bulletin of the Natural Histort Museum. Geology series. 54 J. WATSON, LYDON & HARRISON. Fig. 21 Ovule attributed to Ginkgoites weatherwaxiae sp. nov., Wessex Formation. Worbarrow Bay. Dorset. Apex showing vesicles and distinct longitudinal wall in megaspore membrane cuticle, cell walls of nucellar cuticle and two pollen grains lodged within pollen chamber; x 375. fragment of Ginkgoites weatherwaxiae that its presence was not detected until revealed by maceration. We have decided to attribute it to this species as no features of the ovule are in disagreement with this i
. Bulletin of the Natural Histort Museum. Geology series. 54 J. WATSON, LYDON & HARRISON. Fig. 21 Ovule attributed to Ginkgoites weatherwaxiae sp. nov., Wessex Formation. Worbarrow Bay. Dorset. Apex showing vesicles and distinct longitudinal wall in megaspore membrane cuticle, cell walls of nucellar cuticle and two pollen grains lodged within pollen chamber; x 375. fragment of Ginkgoites weatherwaxiae that its presence was not detected until revealed by maceration. We have decided to attribute it to this species as no features of the ovule are in disagreement with this interpretation. Unfortunately, there are no cuticular characters that can be used to link this structure to this, or indeed to any other, leaf species. If it does not belong to G. weatherwaxiae, it could potentially belong to any of the ginkgoaleans, cycads (Watson & Cusack Drury, in preparation) or numerous unidentified gymno- sperms known from leaf cuticles from the English Wealden. Fig. 20A shows the remaining two layers of cuticle present in this ovule in the light microscope. The ovule is orthotropous, and broken at the chalaza with no evidence of the funicle. The absence of integument cuticles means that there is no direct evidence of the micropyle, and we have no way of knowing if thick flesh or a stony layer existed within the integument. Unfortunately, evidence of the structure of the ovule-bearing organ is also lacking. Following light microscopy, the ovule was first mounted whole on a stub, displaying the damaged nucellar cuticle (Fig. 20B). It was then removed and remounted to allow SEM study of the reverse surface (Fig. 20C). This process revealed the thicker inner cuticle over most of this surface, the delicate nucellar cuticle having been lost. The nucellar cuticle completely envelops the inner cuticle and consists of cells with a smooth outer surface and straight anticlinal walls which are longitudinally aligned and decrease in size towards the micropylar end
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