. The Devonian crinoids of the State of New York. Crinoidea, Fossil; Paleontology; Paleontology. DEVONIAN CRINOIDS OF NEW YORK 335. Species of medium size. Cup a little flattened on the dorsal side; slight constriction just above the middle, above this it expands. The specimen gives the following measurements: width at base, mm; width at median constriction, mm; width at arm bases, mm. Character of the posterior side of the cup shown here by a diagram (figure 54). Dorsal cup. Basals fused to three forming a fairly large, subtriangular convex disk. " Anterior " basal, the
. The Devonian crinoids of the State of New York. Crinoidea, Fossil; Paleontology; Paleontology. DEVONIAN CRINOIDS OF NEW YORK 335. Species of medium size. Cup a little flattened on the dorsal side; slight constriction just above the middle, above this it expands. The specimen gives the following measurements: width at base, mm; width at median constriction, mm; width at arm bases, mm. Character of the posterior side of the cup shown here by a diagram (figure 54). Dorsal cup. Basals fused to three forming a fairly large, subtriangular convex disk. " Anterior " basal, the triangular plate which hinges on the left anterior inferradial and represents the fused left posterior and left anterior basals, well shown. This plate does not enter into the stem articulation. Rest of the basal disk formed, by the posterior and right anterior basals (right posterior basal atrophies) largely concealed by the stem because of the way in which the specimen lies in the rock. The character and relations of these basals may be seen in the accompanying figure. As shown there, the posterior and right anterior basals are bounded for some distance by the large radials. Two simple radials, the anterior and left pos- terior, well shown; large, roughly five-sided and somewhat thickened at the junction of the arm plates. Anterior radial has a length of mm and a width of approximately 7 mm. Left anterior inferradial short and triangular; mm wide, 2 mm high; its base a little concave in the center and straight on each side. Left anterior superradial short, pentagonal, supporting a single simple arm; width mm, height 2 mm. The radials of the posterior side are shown in the accompanying diagram. Fused right posterior and right anterior superradials form a low wide plate, the T-plate which is separated from, the large simple radials by the right anterior inferradial and the radianal (right posterior inferradial). Figure 54 Diagram of pos- terior side of Deltacri- n u
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpaleont, bookyear1923
