A treatise on zoology . Fin. XLVI. Ventral surface of Antedon hifido,diagrammatised from various authori-ties. X 4 diain. As, anus ; 0, mouth ;p, pinnules; s, sacenli; ?(•.;), water-pores. Fig. XLVH. ^?trtical section througli tegmen and under-lying structures of Antedon bifida. Hhows fourpores, with ciliated funnels (c/), piercing theintegument (teg), and communicating by awater-vessel (?(;r) with lacunar vessels (/) in theconnective tissue; of the mesentery (m). Tliefunnels are cut through in different , fibrous layer of integument; c, coelomiccavities ; ij, gut-wall, showing out
A treatise on zoology . Fin. XLVI. Ventral surface of Antedon hifido,diagrammatised from various authori-ties. X 4 diain. As, anus ; 0, mouth ;p, pinnules; s, sacenli; ?(•.;), water-pores. Fig. XLVH. ^?trtical section througli tegmen and under-lying structures of Antedon bifida. Hhows fourpores, with ciliated funnels (c/), piercing theintegument (teg), and communicating by awater-vessel (?(;r) with lacunar vessels (/) in theconnective tissue; of the mesentery (m). Tliefunnels are cut through in different , fibrous layer of integument; c, coelomiccavities ; ij, gut-wall, showing outer fibrouslayer, epithelium, and inner cuticle. (AfterVogt & Jung, 18SG.) Greatly magnified. anus often opens low down on the anterior face of the tube. Thestatement has been definitely disproved for many forms hithertosaid to have such pores. But Wachsmuth & Springer (1897,pi. vii., figs. 2b, 5, 6, 9) support it by figures which, if correct and. Fig. XLVIII. structure of tlie anal tube in an Inadunate Crinoid, Mastigocrimis loreus. 1, plates innormal position, from left edge of distal third of tube ; /, transverse folds connecting the mainaxial ridges, r. 2, plates from the proxiinal third, disturbed and exposing the articular facets(art) of the axial ridge. (After Bather, 1892.) x 10 diam. correctly interpreted, prove it for some species up to the hilt and much further. For they show pores not only on the sutures,but penetrating the plates; not only in the interaxial depressions,but on the axial folds; not only in the tube, but in the dorsalcup. The last organ of which the modifications need be considered I?2 THE CRINOIDEA
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishe, booksubjectzoology
