, INIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS PLATE 38 <strong>ECHINODERMATA</strong>, ARTICLE 3 '1114144111111* • . , 4 „. • , 0. 6 -- --% Jr ,44 tr , ''''' or. g • , °N .,' ..F... ' * .. 0 .• It • ko n• • .. lb ; T., _ . . .. a r f • . r 4" or. • 'LAZY 4#0*4 '.. ''''. . ''', . . . ' t . 11 ! . 1 ( 8 • . • 6- *lt--t I .. - 9 ' 4 FAY- ASTOID STUDIES
-tus BLASTOID STUDIES 109 as result <strong>of</strong> outward migration <strong>of</strong> the deltoid septa and fusion <strong>of</strong> the superdeltoid and cryptodeltoids into an epideltoid. Thus, Schizoblastits may have been derived. Acentrotremites could have been formed from Schizoblastus by atrophy <strong>of</strong> pores along the deltoids, with consequent downward migration <strong>of</strong> the ten spiracles and infolding <strong>of</strong> the radial margins to form a hydrospire plate and numerous pores, with fusion <strong>of</strong> the three basals into one. Deltoblastus probably came from Schizoblastus by outward migration <strong>of</strong> the lancet plate and retrogressive overlap <strong>of</strong> the deltoids by the radials. The Granatocrinidae FAY, n. fam., which contains blastoids having nine spiracles, exhibits diverse trends. The various genera probably came from a form related to Schizotremites, by reduction <strong>of</strong> the number <strong>of</strong> hydrospire folds to three, with retention <strong>of</strong> simple pores along deltoid and radial margins (Lophoblastus), or with loss <strong>of</strong> pores along deltoids and development <strong>of</strong> five pores to each side plate along radial margins (Mesoblastus). The remaining genera (except Calycoblastus) can be derived from Lophoblasttts. One trend is toward Carpenteroblasttts, in which the number <strong>of</strong> hydrospire folds is reduced to two. The trend toward Tanaoblastus involves reduction <strong>of</strong> bydrospires to two, loss <strong>of</strong> pores along deltoid margins, formation <strong>of</strong> a hydrospire plate, and occurrence <strong>of</strong> two pores to each side plate as a result <strong>of</strong> infolding <strong>of</strong> the ambulacral margins <strong>of</strong> the radials. The trend toward Poroblastus from Lophoblastus is marked by reduction <strong>of</strong> the hydrospire folds from three to one, retention <strong>of</strong> simple pores along the deltoid margins, but formation <strong>of</strong> a hydrospire plate and formation <strong>of</strong> multiple pores to each side plate along the radial margins. The trends from Car penteroblas are toward reduction in number <strong>of</strong> folds to a single hydrospire fold on each side <strong>of</strong> an ambulacrum, with downward movement <strong>of</strong> deltoids over the radials (Monoschizoblastus), or toward formation <strong>of</strong> deltoid coronal processes and a concave base (Cribroblastus), from which Heteroblastus could have been derived by downward movement <strong>of</strong> deltoids over the radials. Cal ycoblastus may have been produced from Schizotremites by atrophy or suppression <strong>of</strong> the hypodeltoid. Tanaoblastus probably gave rise to Cryptoblastus as consequence <strong>of</strong> wedge-shaped overlap <strong>of</strong> radials on the deltoids, and to Monadoblastus by atrophy <strong>of</strong> the bydrospire folds to one on each side <strong>of</strong> an ambulacrum, accompanied by development <strong>of</strong> a concave base. The trends from Poroblastus are toward formation <strong>of</strong> multiple pores along deltoid margins, with increase in size (Granatocrintts), or with retention <strong>of</strong> small size and abutment <strong>of</strong> radials against deltoids (Ptychoblastus). Extensive restudy <strong>of</strong> many old-named blastoid species is needed. These are not considered in this paper because types or other specimens are unavailable for study, or time did not permit. For instance, the form known as Orbitremites malaianus from Permian beds <strong>of</strong> the Basleo region in Timor in all probability is a species <strong>of</strong> a new genus if demonstrated to have a simple epideltoid on the anal side instead <strong>of</strong> a superdeltoid and two cryptodeltoids; Tricoelocrintts? belfordi, <strong>of</strong> the Permian Fenestella shale <strong>of</strong> New South Wales, and T.? car penteri, <strong>of</strong> the Permian Gympie beds <strong>of</strong> Queensland, probably also belong to a new genus if shown to possess an cpideltoid instead <strong>of</strong> a superdeltoid and two cryptodeltoids on the anal side; Tricoelocrinus? leai, <strong>of</strong> the Devonian Tor Bay Limestone <strong>of</strong> Devonshire, England, is probably misplaced, actually belonging to some other genus; various species referred to Codaster are judged likely to belong to other genera (e.g., C. blairi, C. curtus, C. gracillirnus, C. grandis, C. gratiosus, C. hindei, C. lorae, and C. superbus); Mesoblasttts attstralis, <strong>of</strong> the Permian Gympie beds <strong>of</strong> Queensland, probably belongs to some EXPLANATION OF PLATE 38 FIGURE PAGE 1-3,5. Tanaoblastus concinnulus (Rawl= & HARE), holotype, one <strong>of</strong> three specimens (figs. 1-3), paratype, polished section (fig. 5), Robert R. Rowley coll., Univ. Illinois; Lower Mississippian, base <strong>of</strong> Lower Burlington Limestone, Louisiana, Mo.; 1-3, oral, "D" ambulacral, aboral views <strong>of</strong> hobotype ( X7): 5, oral view <strong>of</strong> polished section showing hydrospires ( X 8) 103 4. Cryptoblastus shumardi (MEEK & WORTHEN), topotype, S3,765, Springer coll., U.S. Natl. Mus.; Lower Mississippian, Lower Burlington Limestone, Burlington, Iowa; crushed specimen showing form <strong>of</strong> brachioles attached to calyx (X2.8) 61 6-9. Cryptoblastus fnelo (OwEN & SHUMARD)-6. Unlabelled specimen, Philadelphia Acad. Sci. Mus.; ?Mississippian, ?locality; view showing cryptodeltoid (dark calcite) adjacent to lancet plate on right with hypodeltoid partly removed, anal opening black (X14.6). 7-9. Neotype (new holotype), S4,959, Springer coll., U.S. Natl. Mus.; Lower Mississippian, Lower Burlington Limestone, Burlington, Iowa; oral, "D" ambulacral, aboral views (all X 4.4) 61
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