ECHINODERMATA - KU ScholarWorks - University of Kansas

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 of the anal opening, separating the anal
opening from the adjacent spiracles. Thus there are nine
openings around the mouth, consisting of eight spiracles
and the anispiracle. Two hydrospire folds occur on each
side of 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 of 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 of 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 of 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 of Hallsville, Missouri, University
of 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, University of 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 of 10 mm. along an ambulacrum.
Lancet covered by side plates in aboral one-half
of each ambulacrum and exposed almost one-third of its
width near the adorai end. This and other species may
be distinguished by shape of the calyx and relative proportions
of pelvis, vault, length, and width.
Occurrence.—Lower Mississippian, Chouteau Limestone,
9 miles northeast of Osceola, Missouri.
Type.—Holotype, 3,293, Peck collection, University
of 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 of eight
spiracles and the anispiracle. Two hydrospire folds occur
on each side of 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 of 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 of the calyx plates are ornamented
by fine ridges or granular lines subparallel to plate margins.
Occurrence.—Lower Mississippian, lower part of
Burlington Limestone, Louisiana, Missouri.
Types.—Holotype, one complete specimen; paratypes,
one cut section and a specimen in rock, Rowley collection,
Department of Geology, University of 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.