Ovulate cones, averaging 5·0 cm long x }·5 cm wide, borne as single terminal units on vegetative axes with helically arranged simple or bifid leaves. Cones comprised of primary axis with helically arranged bifid bracts and axillary fertile shoots. Fertile shoots bearing twenty-five to thirty sterile scales and one to two fertile scales (rarely three to five) positioned adjacent to primary axis. One terminal inverted ovule per fertile scale. Ovules bilaterally symmetrical and winged, with rounded or cordate base and attenuated micropyle. Nucellus free from integument distal to chalaza. Simple pollen chamber with nucellar beak; often containing Potonieisporites grains. Stomata with five to nine unipapillate subsidiary cells. Adaxial leaf structure with stomata in two parallel bands, each four to eight stomata wide with some shared subsidiary cells; single bands or isolated rows of stomata occurring on some leaves. Abaxial cuticles papillate and less stomatiferous. Unicellular hairs common at margins of leaves and bracts.
Lebachia lockardii sp. nov.
nomenclatorial act:
protologue/first publication
Page:
72
diagnosis:
systematic position:
Coniferales, Lebachiaceae, Lebachia
typeseries:
Holotype. Slides, peels, and remaining portions of specimen M26; reposited in the Palaeobotanical Herbarium, Ohio University, as numbers: 3834-3851; 3867-3912; 3968-4092; 4267, and represented herein as Plate 9, fig. 5; Plate 10, figs. 1-3,5,6; Plate 11, figs. 1,3-6; Plate 12, fig. 4; Plate 13, figs. 1,3,5; Plate 14, figs. 1-8.
Paratypes . Specimens M147 and M148 reposited as above, as numbers 4093-4147; 4234-4251, and 3855-3865; 4160-4218; 4260-4262; 4268, respectively, and figured herein as (MI47) Plate 9, figs. 1,4, and (MI48) Plate 11, figs . 2, 5, 7; Plate 12, figs. 5,7,8; Plate 13, figs. 1,4,6; Plate 15, figs. 1-3,5-7 ; Plate 16, figs. 1-3 .
Classification:
Add new comment