ECHINODERMATA - KU ScholarWorks - University of Kansas

36 THE UNIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS
toward the small round lumen. Radials five, elongate
hexagonal, with almost subparallel sides, each 10 mm.
long by 7 mm. wide, with narrow limbs extended outward
from the calyx into bluntly rounded wings; radials
overlapping deltoids.
Deltoids four, widely lancet-shaped, each 2 mm. long
by 2 to 3 mm. wide, with bulbous adoral end of a
spiracular slit excavated in the middle of each side of
each deltoid. On the anal side a small rounded anal
opening occurs between a 7-sided epideltoid and a 5-sided
hypodeltoid. The expanded ends of the anal spiracular
slits are excavated in the epideltoid. The slits extend as
openings almost one-half the length of each ambulacrum.
Internally, five hydrospire folds occur on each side of an
ambulacrum, each fold opening into each spiracular slit
and ending admedially in a sublancet or fused hydrospire
plate that underlies the lancet and side plates. The anal
opening is covered with about 20 small, flexible, polygonal
plates. The oral opening is surrounded by four deltoid
lips and the epideltoid, and is covered by five large oral
plates that are interradial in position. Radials overlap
deltoids.
Ambulacra five, narrow, linear, with narrow sinus,
1.5 mm. wide, with lancet covered by side plates near
aboral end of lancet but exposed along the middle fourth
of lancet's width along the remainder of each ambulacrum.
Approximately 30 side plates occur in a space of
10 mm. along an ambulacrum, normally disposed, with
lenticular secondary side plates between the primary side
plates, and admedially disposed from the ambulacral margins.
The lancet plates are separated from the oral opening
by the wide deltoid lips. The surfaces of the calyx plates
are ornamented with fine growth striae parallel to plate
margins.
Remarks.—The type-species was presumably in the
Owen collection which was destroyed by fire in 1883 at
Indiana University. The specimen evidently was not in
the Shumard collection, because Hambach had many of
these types when he sold his collection to Springer and
they are not in the collection of the United States National
Museum. Therefore, neotypes have been erected
to replace the destroyed types.
Occurrence.—Lower Mississippian, lower part of Burlington
Limestone, Burlington, Iowa.
Types.—Neotypes, S4,961, two specimens, new holotype
with oral plates in place (figures 4-7, 9) and new
paratype with anal plates in place (figure 8), Springer
collection, old number S3,234, U. S. National Museum,
Washington.
OROPHOCRINUS CAMPANULATUS (Hambach)
Plate 13, figures 1-3
Codonites cam panulatus HAMBACH, 1884, p. 553, pl. D, figs. 8-9.
Description.—Calyx 18 mm. long by 15 mm. wide,
vault 7 mm. long, pelvis 11 mm. long, and pelvic angle
of 50 degrees. In side view, the calyx is broadly clubshaped
and similar to O. stelliformis. The basal circlet
is 4 mm. long, the radial circlet 12 mm. long, each radial
7 mm. wide, and the deltoids are each 2 mm. long. There
are 34 side plates in 10 mm. length of an ambulacrum.
Another fragmentary syntype is 21 mm. long by 16 mm.
wide.
Occurrence.—Lower Mississippian, Chouteau Limestone,
Sedalia, Missouri.
Types.—Syntypes, S3,236, Hambach collection, purchased
by FRANK SPRINGER, one complete specimen and
one fragmentary specimen, U. S. National Museum,
Washington.
OROPHOCRINUS CONICUS Wachsmuth & Springer
Plate 15, figures 1-2
Orophocrinus conicus WACHSMUTH St SPRINGER, 1890, p. 201, pl. 15,
figs. 1-3.
Description.—One specimen is 43 mm. long by 8 mm.
wide (Pl. 15, fig. 1); another is 12 mm. long by 8 mm.
wide (Pl. 15, fig. 2), with a stem 105 mm. long. The
narrow steeply conical form of the calyx and long pelvis
readily distinguish this species from all others.
Occurrence.—Lower Mississippian, Hampton Formation
(Kinderhookian), Le Grand, Marshall County, Iowa.
Types.—Topotypes (metatypes), S3,226, 78 specimens,
Springer collection, U. S. National Museum, Washington.
EXPLANATION OF PLATE 5
FIGURE
PAGE
1-3. Trionoblastus gracilis (WAcHsmu -rx), plesiotype, E21,142,
I. G. Reimann coll., Buffalo Soc. Nat. Sci.; Devonian,
Thunder Bay Limestone, Alpena, Partridge Point, Michigan;
oral, "D" ambulacral, aboral views (all X6) 49
4-6. Trionoblastus alatus (REimANN), plesiotype, 30,736, Univ
Michigan; Potter Farm Formation, shale pit just west of
Evergreen Cemetery, west of Alpena, Michigan; oral view
(showing six amulacra), aboral view, "D" ambulacral
view (all X6.1) 47
7-9. Trionoblastus canadensis (BILLINGS), plesiotype, E11,760,
I. G. Reimann coll., Buffalo Soc. Nat. Sci., Devonian,
"Encrinal limestone," Thedford, Ontario; oral, "D" ambulacral,
aboral views (all X7) 48