88 THE UNIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS cryptodeltoids, and a hypodeltoid on anal side; hydrospire plate present; approximately twice as many pores as side plates along the deltoid and radial margins, one curved or straight hydrospire fold on each side <strong>of</strong> an ambulacrum; deltoids overlap radials, lancet exposed along middle one-third <strong>of</strong> its width; shape <strong>of</strong> calyx elliptical. Lower Carboniferous, England. Remarks.—The genus Orbitremites was probably derived from Ellipticoblastus by overlap <strong>of</strong> radials by the deltoids. ORBITREMITES DERBIENSIS (Sowerby) Plate 44, figures 8-12; text-figs. 179-182 Pentremites derhiensis SOWERBY, 1825, pl. 11, fig. 3. Description.—Calyx calcitic, flattened ellipsoidal in side view, circular in top view, 7.5 mm. long by 7.5 mm. wide, with periphery at mid-height. Stem impression round, 1 mm. in diameter, moderately deep concavity. Basal circlet pentagonal in basal view, 1.5 mm. in diameter, in basal concavity, with three normally disposed basals. Radials five, short, wide, pentagonal in side view, recurved below, each 4 mm. long by 3.5 mm. wide, with short, flat, narrow sinus 3 mm. long by 0.75 mm. wide, and 110 degree angle <strong>of</strong> radial limbs at radiodeltoid suture, with center at interradial suture. Deltoids overlap radials. Deltoids four, long, broadly lancet-shaped, each 6 mm. long by 3.5 mm. wide, pierced in the adorai tip by one oval spiracle, with deltoid lip adjacent to oral opening. On the anal side the anispiracle is between the V-shaped small epideltoid and large elongate pentagonal hypodeltoid, with the two small cryptodeltoids (hidden beneath the hypodeltoid) on either side <strong>of</strong> the anal opening, internally separating the anal opening from the adjacent hydrospire canals. The cryptodeltoids are infolded to form the hydrospires and hydrospire plate on the anal side. The oral opening is surrounded by four deltoid lips and the superdeltoid, and is surrounded by five spiracles, or four spiracles and an anispiracle. One long curved hydrospire fold occurs on each side <strong>of</strong> an ambulacrum, ending admedially in a hydrospire plate. Ambulacra five, linear, each 9 mm. long by 0.75 mm. wide, recurved below, with lancet exposed along the median one-third <strong>of</strong> its width almost to the aboral tip, and approximately 30 side plates in a space <strong>of</strong> 10 mm. along an ambulacrum. The side plates are normally disposed, with a subtriangular outer side plate resting on the abmedial-adoral bevelled corner <strong>of</strong> each primary side plate, two pores to each side plate along the deltoid and 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 minute granules arranged along growth lines subparallel to plate margins. Occurrence.—Lower Carboniferous, Cockleshell beds <strong>of</strong> the Middle Limestone <strong>of</strong> Yarnbury, near Grassington, Yorkshire, England. Types.—Plesiotypes, 328, 4, 5, one unnumbered (four specimens), Harold Beaver collection, sent by DR. JOYSEY, from Cambridge; Humble Oil & Refining Co., Houston, Texas. The description is mainly that <strong>of</strong> specimen 328. ORBITREMITES CAMPANULATUS (M'Coy) Plate 43, figures 4-6; text-figs. 183-185 Pentrenutes cam panulatus M'Coy, 1849, p. 249; 1854, p. 123, pl. 3-D, fig. 9. Description.—Calyx calcitic, fragmentary, 7.5 mm. wide, with flat base, and periphery just above base. Stem round, crenellar, 1 mm. in diameter, with approximately 30 crenellae, and a small central round lumen. Basal circlet pentagonal in aboral view, 2 mm. wide, in broad basal concavity. Radials five, pentagonal in side view, presumably reaching to one-half the height <strong>of</strong> the calyx, each 5.5 mm. long by 4 mm. wide, recurved below, with a long, narrow, shallow sinus 5 mm. long by 1.25 mm. wide. Upper portion <strong>of</strong> calyx destroyed but presumably like O. ellipticus, with four deltoids, and a superdeltoid, two cryptodeltoids, and hypodeltoid, and five spiracles. Hydrospire plate present along deltoid and radial margins, with two pores to each side plate and one long straight hydrospire fold on each side <strong>of</strong> an ambulacrum. Deltoids overlap radials. An angle <strong>of</strong> 115 degrees is formed by the radial limbs at the radiodeltoid suture, FIGURE EXPLANATION OF PLATE 27 PAGE 1-11. Eleutherocrinus cassedayi SHUNIARD & YANDELL, Middle Devonian, Hungry Hollow Formation (coral zone <strong>of</strong> Widder beds), near Thedford, Ontario.-1 5. Plesiotype, E15,933, Charles Southworth coll., Buffalo Soc. Nat. Sci.; old quarry on Frank Hunniford farm near Thedford, Ontario; 1, oral view ( X4.5); 2, "D" ambulacral view ( X4.1); 3, aboral view ( X4.3); 4, "B" ambulacral view ( X4.3); 5, "C" atnbulacral view ( X5)-6 8. Plesiotypes, E13,061, Charles Southworth coll., Buffalo Soc. Nat. Sci.; 6, aboral view <strong>of</strong> polished section <strong>of</strong> "E" ambulacrum ( X10); 7, view looking adorally <strong>of</strong> polished section <strong>of</strong> "D" ambulacrum <strong>of</strong> another specimen ( X 11) ; 8, aboral view <strong>of</strong> an ambulacrum near aboral end <strong>of</strong> another specimen, showing thick radial plate beneath lancet ( X15). 9 11. Plesiotype, 3,665, Geol. Survey Canada; 9, "D" ambulacral view ( X3.7); 10, 11 , oral and aboral views (X4.1) 72
I TNIVERSEI Y OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS <strong>ECHINODERMATA</strong>, ARTICLE 3 PLATE 27 1 FAY-BLASTOID STUDIES
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