. Early Llandovery crinoids and stelleroids from the Cataract Group (Lower Silurian) in southern Ontario, Canada . B Text-fig. 16A-C Protaxocrinus cataractensis sp. nov. Radials black; radianal ruled; anal X wrinkle stipple; higher anals dot stipple. Scales 10 mm. A Anterior view of holotype, showing irregular perisomic plates. ROM 39003, PI. 8, fig. 8. B CD-interray of holotype. Proximal portion of anal tube is sutured to C-ray. ROM 39003, PI. 8, fig. 7. C Anterior view of individual centred on A-ray. A-ray has three primibrachials; B- and E-rays each have two primibrachials. Paratype ROM 390
. Early Llandovery crinoids and stelleroids from the Cataract Group (Lower Silurian) in southern Ontario, Canada . B Text-fig. 16A-C Protaxocrinus cataractensis sp. nov. Radials black; radianal ruled; anal X wrinkle stipple; higher anals dot stipple. Scales 10 mm. A Anterior view of holotype, showing irregular perisomic plates. ROM 39003, PI. 8, fig. 8. B CD-interray of holotype. Proximal portion of anal tube is sutured to C-ray. ROM 39003, PI. 8, fig. 7. C Anterior view of individual centred on A-ray. A-ray has three primibrachials; B- and E-rays each have two primibrachials. Paratype ROM 39005, PI. 8, fig. 5. curved (PI. 8, fig. 9). Radianal pentagonal, with height equal to width, lying below C-ray radial, adjoining anal X and BD-inteiray basals. Anal X hexagonal, with height equal to width, adjoining C- and D-ray radials and the underlying basal. Anal tube long, narrow; proximal portion sutured to C-ray. Proximal anal plates irregular, polygonal, becoming smaller and more numerous distally (Text-fig. 16B; PI. 8, fig. 7). Interbrachials small, diamond-shaped, overlying truncated distal facets of radials (PI. 8, fig. 3), incorporated into cup, followed by irregular perisomic plates that become smaller distally and extend beyond secundaxillaries (Text-fig. 16A; PI. 8, figs. 3, 9). Arms composed of smooth, rounded brachials with gently curved sides. Proximal brachials wider than high; distal brachials equidimensional to twice as high as wide. Proximal brachials of adjacent rays not in contact. Sutures between brachials slightly sinuous, depressed. Axillaries pentagonal, with gently to strongly curved distal facets that each produce a spear-shaped projection. Distal width of axillary slightly greater than its proximal width. Arms branching isotomously three or four times. Primibrachials two or three per taxis—variation in individuals. Secundi- brachials three to five; tertibrachials six to 12; quartibra- chials absent or few in number. Distal portions of arms not pr
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Keywords: ., bookcentury1900, bookd, bookleafnumber42, booksubjectpaleontology
