Smithsonian miscellaneous collections . pecies.—Lecanocrinus tnacropetalus Hall, —Silurian and Devonian. Subgenus LECANOCRINUS (sensu stricto) Hall, 1852 Lecanocrinids with the RA and X well developed, IBB erect andvisible from the sides. The arms are free above the IBrr, are relativelylong, not tightly coiled upon themselves at distal ends, and tend to di-chotomize unequally. Type species.—Same as for the genus Lecanocrinus. Range.—Silurian. Subgenus GEROLDICRINUS Jaekel, 1918 Lecanocrinids with the anal X well developed but RA much re-duced by resorption, IBB subhorizontal and nea
Smithsonian miscellaneous collections . pecies.—Lecanocrinus tnacropetalus Hall, —Silurian and Devonian. Subgenus LECANOCRINUS (sensu stricto) Hall, 1852 Lecanocrinids with the RA and X well developed, IBB erect andvisible from the sides. The arms are free above the IBrr, are relativelylong, not tightly coiled upon themselves at distal ends, and tend to di-chotomize unequally. Type species.—Same as for the genus Lecanocrinus. Range.—Silurian. Subgenus GEROLDICRINUS Jaekel, 1918 Lecanocrinids with the anal X well developed but RA much re-duced by resorption, IBB subhorizontal and nearly confined to the NO. 9 NEW DEVONIAN CRINOID BOVVSHER basal concavity. The arms are short, not coiled upon themselves atdistal ends, and divide only twice isotomously. Type species.—Lecanocrinus {Geroldicrinus) roemeri (Schultze). Range.—Middle Devonian. MIRACRINTJS Bowsher, new subgenus Diagnosis.—A lecanocrinid with a bowl-shaped cup, IBB hidden inbasal concavity by the column, with the arms suturally united laterally. Fig. I.—Diagrams showing the typical structures of Lecanocrinus () andLecanocrinus (Miracrinus) Bowsher, new subgenus. a. Diagram of the cup of Miracrinus showing the IBB, BB, RR (solid black),RA, and anal X, X i- b. Diagram showing the posterior interradius of the holo-type of Lecanocrinus (Miracrinus) perdczvi, the type species of the subgenusMiracrinus ( No. 118033), X i- -f is at the level of the R-IBr suture,top of the cup, and y is at the top level of sutural union of the brachials of theposterior rays, X i- c, Top view of Lecanocrinus (Miracrinus) perdetm showingthe structure of the distal parts of the rays, X i- d, Reconstruction of the leftanterior ray of Lecanocrinus (Miracrinus) perdewi, X i- j* is at the top levelof sutural union in the crown, e. Reconstruction of the dorsal cup of Lecano-crinus (Miracrinus) perdewi showing the IBB hidden in the basal cavity, X i-/, Reconstruction of the dorsal cup of Lecanocrinus (Leca
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Keywords: ., bookauthorsm, bookcentury1800, bookdecade1860, booksubjectscience
