. Bulletins of American paleontology. 20 Bulletin 185 1946, pi. 2, figs, la, h) are imperfectly understood, it appears to conform to the conventional mitrate organization (see Caster, 1952, jfig. 2A, B). The Syringocr'nii/s stele is far too generalized to fit into the Mitrata scheme. Moreover, the many small polygonal plates which Bather revealed at the proximal end of the specimen fortify the assignment to the Soluta-Dendro- cystitidae. Family lOWACYSTIDAE Gill and Caster, new family —Soluta u'ith di-jferentiated anal and antianal thecal faces, one having jew syiuinetrically organi
. Bulletins of American paleontology. 20 Bulletin 185 1946, pi. 2, figs, la, h) are imperfectly understood, it appears to conform to the conventional mitrate organization (see Caster, 1952, jfig. 2A, B). The Syringocr'nii/s stele is far too generalized to fit into the Mitrata scheme. Moreover, the many small polygonal plates which Bather revealed at the proximal end of the specimen fortify the assignment to the Soluta-Dendro- cystitidae. Family lOWACYSTIDAE Gill and Caster, new family —Soluta u'ith di-jferentiated anal and antianal thecal faces, one having jew syiuinetrically organized plates, and the other many poly- gonal plates: theca triangular in outline, conipressed. Brachiole distal but not Text-fig. —loicacystis sagittariu Thomas and Ladd, from the Upper Ordovician (Maquoketa shale) of Iowa. Traced from Thomas and Ladd, 1926. Coniment.—Thomas and Ladd (1926) wrote, "This genus exhibits a group of characters which place it close to the family Anomalocystidae and to which it is provisionally referred. However, the triangular outline of the theca, its stem characters, plate markings and single oral process located outside the sagittal plane are foreign to the family. Foerste (1917) sug- gested relationship to the Mitrocystidae or Lagynocystidae. The genus may eventually be relegated to a new ; Bather (1928) referred the species to "Dendrocystis'. Dehm (1934) preferred to rank lowacystis as at least a subgenus of Dendrocystites. The present authors consider Thomas and Ladd correct in making a new genus because the organization of this car- poid is unique, as they pointed out. However, they agree with Bather and Bassler that its affinities are with the Dendrocystites lineage (see text-figure. 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 P
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