UNIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIFIVTIONS PLATE 16 <strong>ECHINODERMATA</strong>, ARTICLE 3 FAY BLASTOID STUDIUS
BLASTOID STUDIES 61 CRYPTOBLASTUS MELO (Owen & Shumard) Plate 38, figures 6-9; text-figs. 98-100 Pentremites melo OWEN & SHUMARD, 1850, p. 65, pl. 7, figs. 14a-c. Description.—Calyx calcitic, subspherical, 13 mm. long by 11 mm. wide, with truncated summit and depressed base. Stem round, 1 mm. in diameter, with approximately 40 crenellae extending almost one-half the radial distance in from the circumference. Basal circlet pentagonal, 3 mm. wide, depressed in basal concavity, with three normally disposed basals. Radials five, elongate, recurved below, each 12 mm. long by 5.5 mm. wide, with narrow sinus and depressed interradial sutures; radials overlapping deltoids except at the adoral tip <strong>of</strong> radial limbs where in reverse manner aboral ends <strong>of</strong> the deltoid bodies slightly overlap the radial limbs, giving the appearance that the radial limbs are wedged in the deltoid bodies. Deltoids four, arrow-shaped, each 1.5 mm. long by 1.5 mm. wide, with two spiracles notched in the adoral tip <strong>of</strong> each on the ambulacral margins, and without pores along margins <strong>of</strong> the ambulacra. On the anal side a large oval anispiracle occurs between an epideltoid and hypodeltoid, but internally, in a specimen seen in the Philadelphia Academy <strong>of</strong> Sciences collection, there probably are two hidden cryptodeltoids beneath the hypodeltoid. If this is true, the plate adjacent to the oral opening on the adorai side <strong>of</strong> the anal opening should probably be called the superdeltoid, instead <strong>of</strong> epideltoid. Ambulacra five, linear, each 15 mm. long by 1.25 mm. wide, recurved below, lancet exposed along the middle one-third <strong>of</strong> its width except at the aboral end. The side plates are normally disposed with 30 side plates in a space <strong>of</strong> 10 mm. length along an ambulacrum. Four coverplate sockets to each side plate are seen along the main food groove and three side cover-plate sockets to each side plate along side food grooves. Two hydrospire folds occur on each side <strong>of</strong> an ambulacrum, with a hydrospire plate on each side, and more pores than side plates (approximately two to each side plate) along the radial margins. The surfaces <strong>of</strong> the calyx plates are ornamented with fine granules aligned parallel to plate margins. The above description is based on the newly selected holotype. Remarks.—The original holotype was destroyed in a fire at Indiana <strong>University</strong> in 1883, where the Owen collection was housed. The neotype, or new holotype, here selected, is that figured by ETHERIDGE & CARPENTER, 1886, pl. 7, fig. 14. Occurrence.—Lower Mississippian, lower part <strong>of</strong> Burlington Limestone, Burlington, Iowa (neotype). Type.—Neotype (new holotype), S4,959, one specimen, old number S3,766, Springer collection, U. S. National Museum, Washington. This is also the type-species <strong>of</strong> Cry ptoblastus. CRYPTOBLASTUS SHUMARDI (Meek &Worthen) Plate 38, figure 4 Granatocrinus shumardi MEEK & WORTHEN, 1866, p. 257. Description.—The specimen is 36 mm. long by 17 mm. wide and is here illustrated to show the shape <strong>of</strong> the specimen with brachioles attached. Occurrence.—Lower Mississippian, lower part <strong>of</strong> Burlington Limestone, Burlington, Iowa. Types.—Topotypes, S3,765, 10 specimens, Springer collection, U. S. National Museum, Washington. Genus DEVONOBLASTUS Reimann, 1935 Type-species, by subsequent designation (Reimann, 1942) —l'entremites leda HALL, 1862. Generic diagnosis.—Spiraculate blastoids with five spiracles, or four spiracles in addition to an anispiracle, with anispiracle between a superdeltoid and hyperdeltoid and with two hidden cryptodeltoids, approximately five hydrospire folds on each side <strong>of</strong> an ambulacrum, lancet covered by side plates except at adoral end, with one pore between side plates along radial and part <strong>of</strong> deltoid margins; deltoids visible in side view, overlapped by radials; calyx form elliptical, with conical pelvis. Devonian, New York, Ontario, ?Indiana. Remarks.—The genus Devon oblastus was probably derived from Hyperoblastus by complete closure <strong>of</strong> the radial sinus, downward migration <strong>of</strong> the deltoid plates, and partial outward migration <strong>of</strong> the adorai end <strong>of</strong> the lancet plates. EXPLANATION OF PLATE 16 FIGURE PAGE 1-3. Orophocrinus gracilis (MEEK & WORTHEN), topotypes, S3,228, Springer coll., U.S. Natl. Mus.; Lower Mississippian, Lower Burlington Limestone, Burlington, Iowa; 1, oral view <strong>of</strong> specimen ( X4.4); 2,3, aboral and "D" ambulacral views <strong>of</strong> another specimen ( X3.6) 37 4-6. Orophocrinus orbignyanus (DE KoNnvcx), topotype, S3,229, Springer coll., U.S. Natl. Mus.; Lower Carboniferous limestone, Tournai, Belgium; 4, oral view, ( X3.5); 5, "B" ambulacral view, ( X2.8); 6, aboral view, ( X3.7) 37 7-9. Orophocrinus verus (CUMBERLAND), plesiotype, S3,237, Springer coll., U.S. Natl. Mus.; Lower Carboniferous limestone, Lancashire, England; oral, "D" ambulacral, aboral views (all X3.5) 39 10-12. Orophocrinus puzos (MONSTER), topotype, S3,230, Springer coll., U.S. Natl. Mus.; Lower Carboniferous limestone, Tournai, Belgium; oral, "D" ambulacral, aboral views (all x6.6) 38