. Early Llandovery crinoids and stelleroids from the Cataract Group (Lower Silurian) in southern Ontario, Canada . B Text-fig. 12A-D Cataractocrinus dementi gen. et sp. nov. Inferradials and superradials black; anal X wrinkle stipple; higher anals dot stipple; A, B scales 5 mm; C, D scales 1 mm. A Holotype centred on C-ray. Note long anal appendage and isotomous branching of arms, incomplete in this individual. Basals of this specimen are missing. ROM 39011, PI. 5, fig. 1. B Anterior view of typical individual. Basals of this specimen are missing. Paratype ROM 39012, PI. 5, fig. 2. C Anterior
. Early Llandovery crinoids and stelleroids from the Cataract Group (Lower Silurian) in southern Ontario, Canada . B Text-fig. 12A-D Cataractocrinus dementi gen. et sp. nov. Inferradials and superradials black; anal X wrinkle stipple; higher anals dot stipple; A, B scales 5 mm; C, D scales 1 mm. A Holotype centred on C-ray. Note long anal appendage and isotomous branching of arms, incomplete in this individual. Basals of this specimen are missing. ROM 39011, PI. 5, fig. 1. B Anterior view of typical individual. Basals of this specimen are missing. Paratype ROM 39012, PI. 5, fig. 2. C Anterior view of only individual found attached to its column. Paratype ROM 39017, PI. 5, fig. 9. D Anterior view of crushed specimen. Basals are missing. Paratype ROM 39016, PI. 5, fig. 7. the anal structure to the adjacent arms on this genus support the hypothesis. Differentiation of the first anal plate, however, had already occurred in unrelated genera by the Middle Ordovician. Cataractocrinus dementi sp. nov. Text-fig. 12A-D; PI. 5, figs. 1-9 TYPE MATERIAL Ten specimens were available for study: holotype ROM 39011; paratypes figured ROM 39012 to 39014 inclusive. ROM 39016 to 30919 inclusive; paratypes unfigured ROM 39015, 39048. OCCURRENCE Cabot Head Formation, m above base, at Ball's Falls on Twenty Mile Creek near Jordan, Ontario. ETYMOLOGY The specific name refers to the discovery of this species by Mr. Craig Clement, a graduate student at the University of Tennessee at Knoxville. He found the specimens in difficult collecting conditions near the base of Ball's Falls. 27
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Keywords: ., bookcentury1900, bookdecade1980, bookspo, booksubjectpaleontology
