. Early Llandovery crinoids and stelleroids from the Cataract Group (Lower Silurian) in southern Ontario, Canada. Crinoidea, Fossil; Starfishes, Fossil; Paleontology; Paleontology. anal plates equal; maximum widths of distal anal plates equal one-half of heights. Distal portion of anal appendage not preserved. Arms five, uniserial, apinnulate, branching at least three times. First bifurcation isotomous; higher bifurcations strongly heterotomous (Text-fig. 13A, B; PI. 6, figs. 1, 2). Primibrachials three to six per taxis; last brachial in each taxis axillary. Secundibrachials four to six per ta
. Early Llandovery crinoids and stelleroids from the Cataract Group (Lower Silurian) in southern Ontario, Canada. Crinoidea, Fossil; Starfishes, Fossil; Paleontology; Paleontology. anal plates equal; maximum widths of distal anal plates equal one-half of heights. Distal portion of anal appendage not preserved. Arms five, uniserial, apinnulate, branching at least three times. First bifurcation isotomous; higher bifurcations strongly heterotomous (Text-fig. 13A, B; PI. 6, figs. 1, 2). Primibrachials three to six per taxis; last brachial in each taxis axillary. Secundibrachials four to six per taxis. One additional branching observed on fifth tertibrachial of holotype (ROM 39026). Heights and widths of proximal brachials equal; widths of distal brachials one-third of heights. Arms incompletely preserved. Proxistele heteromorphic, round; diameter one-half that of cup. Lumen of proxistele columnals round; diameter one-third that of stem. Heights of proxistele and mesistele columnals one-quarter to one-third of widths. Mesistele columnals pentagonal with concavopentastellate lumen and five distinct pentameres; each pentamere with small, circular axial 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 Eckert, James D. , 1952-; Royal Ontario Museum. Toronto : Royal Ontario Museum
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Keywords: ., bookcentury1900, bookd, bookleafnumber36, booksubjectpaleontology
