102 THE UNIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS Basal circlet convex outward, pentagonal in aboral view, 1.5 mm. wide, with raised margins and depressed interbasal sutures, and raised pentagonal aboral portion adjacent to stem, with three normally disposed basals. Radials five, each 5 mm. long by 3 mm. wide, with sinus 4 mm. long by 0.75 mm. wide, and 115-degree angle formed by radial limbs at radiodeltoid suture with center at interradial suture. Radials overlap deltoids. Deltoids four, short, each 2.5 mm. long by 1.5 mm. wide, notched in the adoral tip by two spiracles, adjacent to the ambulacra. On the anal side the anal opening is confluent with adjacent spiracles, thus forming an anispiracle. The anispiracle is located between a small U- shaped superdeltoid and a pentagonal hypodeltoid, with two small hidden cryptodeltoids beneath the hypodeltoid on either side <strong>of</strong> the anal opening, separating the anal opening from the adjacent spiracles. Thus there are nine openings around the mouth, consisting <strong>of</strong> eight spiracles and the anispiracle. Two hydrospire folds occur on each side <strong>of</strong> an ambulacrum, ending admedially in a hydrospire plate. Pores are absent along the deltoid margins. Ambulacra five, linear, narrow, each 7 mm. long by 1 mm. wide, with lancet exposed along immediate food groove and 35 side plates in a space <strong>of</strong> 10 mm. along an ambulacrum. Side plates normally disposed, the primary side plate being subquadrangular and the outer side plate subtriangular, resting upon the adoral-abmedial bevelled corner <strong>of</strong> the primary side plate. Approximately two pores to each side plate are seen along the radial margins, and five cover-plate sockets to each side plate along the main food groove. The surfaces <strong>of</strong> the calyx plates are ornamented by coarse growth ridges subparallel to plate margins. The above description is mainly based on hypotype 1,143. Occurrence.—Lower Mississippian, Chouteau Limestone, near Sedalia and Hallsville, Missouri. Types.—Hypotype, 1,143, one specimen, Blair collection, from Sedalia; 1,063, one ground specimen, Peck collection, 3.5 miles west <strong>of</strong> Hallsville, Missouri, <strong>University</strong> <strong>of</strong> Missouri, Columbia; these specimens are labelled Cryptoblastus roemeri; plesiotypes, 19,106, from Sedalia, Gurley collection, 11 specimens identified as Cry ptoblastus roemeri by PECK but labelled Orbitremites roemeri, Walker Museum, <strong>University</strong> <strong>of</strong> Chicago. TANAOBLASTUS BELLATULUS (Peck) Plate 37, figures 4-6 Cryptoblastus bellatulus PECK, 1938, P. 68, pl. 26, figs. 1-3. Description.—Calyx globular, 3.5 mm. long by 2.5 mm. wide, with periphery above center, convex base, linear ambulacra each 4 mm. long by 0.75 mm. wide, with 35 side plates in a space <strong>of</strong> 10 mm. along an ambulacrum. Lancet covered by side plates in aboral one-half <strong>of</strong> each ambulacrum and exposed almost one-third <strong>of</strong> its width near the adorai end. This and other species may be distinguished by shape <strong>of</strong> the calyx and relative proportions <strong>of</strong> pelvis, vault, length, and width. Occurrence.—Lower Mississippian, Chouteau Limestone, 9 miles northeast <strong>of</strong> Osceola, Missouri. Type.—Holotype, 3,293, Peck collection, <strong>University</strong> <strong>of</strong> Missouri. TANAOBLASTUS CONCINNULUS (Rowley & Hare) Plate 38, figures 1-3, 5; text-figs. 214-217 Granatocrinus concinnulus ROWLEY & HARE, 1891, p. 117, pl. 3, figs. 13-14. Orbitremites concinnulus BATHER, 1899, p. 25. Cryptoblastus concinnulus ROWLEY, 1900, pp. 246, 251. Description.—Calyx flattened elliptical in side view, 8 mm. long by 7 mm. wide, with rounded summit and flat base, periphery above mid-height. Stem round, crenellar, 0.75 mm. in diameter, with about 25 crenellae extending radially inward about half-way from the circumference. Basal circlet flat, pentagonal in basal view, 2 mm. in diameter, with depressed basiradial sutures and azygous basal in (DE) interradial position. Radials five, each 7 mm. long by 4 mm. wide, recurved below, with prominent radial lip and narrow, shallow sinus 7 mm. long by 1-1.5 mm. wide; radials overlapping deltoids. Deltoids four, short, lancet-shaped, each with two spiracles notched in the adoral tip along ambulacral margins. On the anal side the anispiracle is between a pentagonal superdeltoid and a pentagonal hypodeltoid, probably with two hidden cryptodeltoids. Thus there are nine openings around the mouth, consisting <strong>of</strong> eight spiracles and the anispiracle. Two hydrospire folds occur on each side <strong>of</strong> an ambulacrum, ending admedially in a hydrospire plate. Pores absent along deltoid margins. Ambulacra five, long, linear, recurved below, with lancet exposed along food groove adorally, and 30 side plates in a space <strong>of</strong> 10 mm. along an ambulacrum. The side plates are normally disposed, with two pores to each side plate along the radial margins, and five main coverplate sockets to each side plate along the main food groove. The surfaces <strong>of</strong> the calyx plates are ornamented by fine ridges or granular lines subparallel to plate margins. Occurrence.—Lower Mississippian, lower part <strong>of</strong> Burlington Limestone, Louisiana, Missouri. Types.—Holotype, one complete specimen; paratypes, one cut section and a specimen in rock, Rowley collection, Department <strong>of</strong> Geology, <strong>University</strong> <strong>of</strong> Illinois. TANAOBLASTUS HAYNESI (Clark) Plate 37, figures 7-9 Schizoblastus haynesi T. H. CLARK, 1917, p. 371, pl. 1, figs. 15-20. Mesoblastus haynesi FRITZ & CLINE, 1937, pp. 307-312, pl. 17, figs. 1-13. Description.—The holotype is 7 mm. long by 6 mm.
BLASTOID STUDIES 103 212 FIGURES 209-217. Species <strong>of</strong> Tanaoblastus FAY, n. gen., Mississippian North America. 209-213. T. roemeri (SHumikan), Chouteau Limestone, near Sedalia and Hallsville, Mo. (Univ. Missouri, nos. 1,063, 1,143; Univ. Chicago, no. 19,106); 209, anal area, drawn from polished tangential section (no. 19,106), X15; 210, cross section <strong>of</strong> "B" ambulacrum, oral view (no. 19,106), X15; 211, partial cross section <strong>of</strong> "D" ambulacrum, aboral view (no. 1,063), X45; 212, partial cross section <strong>of</strong> "B" ambulacrum, aboral view (no. 1,063), X45; 213, part <strong>of</strong> "D" ambulacrum, showing side plates (no. 1,143), X45. 214-217. T. concinnulus (RowLEy & HARE), Burlington Limestone, Louisiana, Mo. (Univ. Illinois, nos. RX206, RX206a); 214, anal area <strong>of</strong> holotype, X15; 215, basal circlet <strong>of</strong> holotype, X15; 216, cross section <strong>of</strong> ambulacrum, X15; 217, part <strong>of</strong> "B" ambulacrum, showing side plates, X45. [Explanation.—"A," amb.; An, anal opening; "B," amb.; Bf, brachiolar facet; Bp, brachiolar pit; "C," amb.; C, canal (radial); CR, cryptodeltoid; "D," amb.; D, deltoid; "E," amb.; HD, hypodeltoid; HP, hydrospire plate; L, lancet; 0, oral opening; OSp, outer side plate; P, pore; Pf, pore furrow; R, radial; RI, radial limb; S, spiracle; Sp, main side plate; Su, superdeltoid; Z, azygous basal.]
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