. The Devonian crinoids of the State of New York. Crinoidea, Fossil; Paleontology; Paleontology. B tral sac in Fistulate crinoids Figure 21 a, Marsipocrinus striatals (?). been found piercing the ven- Diagram of one ray of a specimen showing position of pinnule openings and ambulacra leading to them, x 3/2. B, Scyphocr inus gorbyi. An interradius with / gprixicer 1QOO). adjacent arm-bases showing pores in plates corresponding in position to pinnule ossicles, x 5/2. (After Springer, 191-)- In the Camerata so-called respiratory pores" have been observed near the arm-bases (figure 21). They
. The Devonian crinoids of the State of New York. Crinoidea, Fossil; Paleontology; Paleontology. B tral sac in Fistulate crinoids Figure 21 a, Marsipocrinus striatals (?). been found piercing the ven- Diagram of one ray of a specimen showing position of pinnule openings and ambulacra leading to them, x 3/2. B, Scyphocr inus gorbyi. An interradius with / gprixicer 1QOO). adjacent arm-bases showing pores in plates corresponding in position to pinnule ossicles, x 5/2. (After Springer, 191-)- In the Camerata so-called respiratory pores" have been observed near the arm-bases (figure 21). They occur in the interradii or between the arms and their branches. In the genus Dolatocrinus1 there are four to six in each interradius and two to f our between each series of fixed secundibrachs; some genera have only ten pores. It has now been demonstrated (^Springer, 1917, pp. 40-46) that these pores connect with the food canals. The pores originated from pinnules which with progressive growth were incorporated into the body. These pinnules may have possessed a res- piratory function, since the proximal pin- nules in manv recent crinoids are shown to. Figure 22 A, simple unbranched arm (Hybocrinus). B, ventral view of two brachials of Gissocrinus squami- f e r ; covering plates, or ambulacrals, closed above, removed below. C, side view of brachials of Antedon basi- c u r v a with covering plates open show- ing tentacles. R, radial; Br, brachial; , covering plates or ambulacrals; , side plates or adambulacrals; t, tentacles; , axial canal. (After Bather, 1900). be lacking the usual functions of pinnules. Extreme aberrant growth of pore or pinnule is seen in Gilbertso 1 See discussion of genus Comanthoerinus, page 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 Goldring, Winifred, 1888-1971. A
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpaleont, bookyear1923
