ECHINODERMATA - KU ScholarWorks - University of Kansas

44 THE UNIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS
opening, covered by a few large side plates; shape of
calyx in side view like a cup, with three basals. Permian,
Timor Island, East Indies.
Remarks.—The genus Pterotoblastus was probably
derived from a form similar to Codaster in which the
hydrospire slits had become atrophied to a few in each
field, the hydrospire fields reduced to small areas on
the summit, and the radial plates developed into winglike
extensions.
PTEROTOBLASTUS GRACILIS Wanner
Plate 18, figures 10-11; text-fig. 51
Pterotoblastus gractlis WANNER, 1924, P. 10, text-figs. 1-2, pl. 199,
figs. 11-18.
Description.—The description is the same as that for
the genus. The specimen is approximately 8 mm. long
by 11 mm. wide. Of importance here is the fact that there
are three normally disposed basal plates and not one
plate, as previously reported. This is based on examination
of five almost perfect specimens recently received
from Indonesia.
Occurrence.—Upper Permian, Basleo beds, from
Tonino, Kioe Kilo, near Basleo, Timor Island, Indonesia.
Type.—Topotype, S4,035, one specimen, Springer
collection, U. S. National Museum, Washington.
Genus SAGITTOBLASTUS Yakovlev, 1937
Type-species, by original designation.—Timoroblastus wanneri
YAKOLEV, 1926.
Generic diagnosis.—Fissiculate blastoids with eight
small deep exposed hydrospire fields, with two or
three hydrospire slits in each hydrospire field, hydrospire
fields on summit, with large epideltoid on anal
side and anal opening between radial limbs and epideltoid,
with perhaps a small ?hypodeltoid (missing) on
the aboral side of the anal opening, extremely short
lancet plates covered by large side plates, well away
from oral opening; calyx form spherical in side view.
Permian, Russia.
Remarks.—The genus Sagittoblastus was probably
derived from a form similar to Codaster in which the
hydrospire fields are reduced in size to small, deep
constrictions, the hydrospire slits reduced in number
in each field, and the form changed to spherical, with
consequent shortening of the lancet plates and migration
of lancets away from the oral opening.
SAGITTOBLASTUS WANNERI (Yakovlev)
Plate 18, figures 1-7; text-figs. 52-55
Timoroblastus wanneri YAKOLEV, 1926, pp. 54-55, text-fig. 5, pl. 1,
figs. 8-10.
Description.—Calyx calcitic, subglobular in side view,
rounded pentagonal in top view, 11 mm. long by 10 mm.
wide, with slightly flattened summit, convex base, and
periphery near mid-height. Stem impression not well preserved,
but appears to be round, 0.75 mm. in diameter,
and in a basal concavity. Basal circlet wide, rounded
pentagonal, 3.5 mm. high by 8.5 mm. wide, with three
large normally disposed basais. Radials five, elongate
hexagonal, each 7 mm. long by 5 mm. wide, with short,
flat to deeply concave radial sinus 1.5 mm. long by 1 mm.
wide, with short, flat to deeply concave radial sinus 15
mm. long by 1 mm. wide, almost confined to summit.
Deltoids appear to overlap radial limbs.
Deltoids four, strongly arrow-shaped, each 2.5 mm.
long by 2.5 mm. wide, with two deep concave hydrospire
fields near adjacent ambulacral margins in the aboral part
of the deltoid body, with two or three hydrospire slits in
each hydrospire field parallel to the ambulacra and extending
across the radiodeltoid suture. On the anal side
a large hexagonal epideltoid is found, with the anal opening
between it and the adjacent radial limbs, hydrospire
slits lacking. It is assumed that a small hypodeltoid plate
was present on the anal side, adjacent to the radial limbs,
but washed away. Thus there are nine openings around
the oral aperture, consisting of eight deep hydrospire fields
and a separate anal opening. The deltoid lips and epideltoid
surround the oral opening, and the lancet plates
are displaced away from the oral opening.
Ambulacra five, short, diamond-shaped, each 3 mm.
long by 1.5 mm. wide, with lancet covered by side plates,
EXPLANATION OF PLATE 9
FIGURE PAGE
1-3. Hyperoblastus cummingsi (ItEimANN), hypotype, E15,935,
Buffalo Soc. Nat. Sci.; Devonian, Hungry Hollow Formation
(coral zone of Widder beds), Arkona, Ontario; oral,
"D" ambulacral, aboral views (all X4.4) 31
4-6. Hyperoblastus southworthi (REIMANN), holotype, E11,816,
Charles Southworth coll., Buffalo Soc. Nat. Sci.; Devonian,
Hungry Hollow Formation (coral zone of Widder
beds), tile yard, Thedford, Ontario; oral; "D" ambulacral,
aboral views (all X7.8) 35
7, 9- 11. Hyperoblastus dotis (REImANN), holotype, E15,401,
(figs. 9-11); paratype, E13,052, (fig. 7); Buffalo Soc. Nat.
Sci.; Devonian, Hungry Hollow Formation (coral zone
of Widder beds), Thedford, Ontario; 7, cross sec. "E"
arnbulacrum ( X6.5); 9-11, oral; "D" ambulacral, aboral
views ( X8)
8. Hyperoblastus filosus angustus (REIMANN), holotype,
E15,403, Buffalo Soc. Nat. Sci.; Devonian, Hungry Hollow
Formation (coral zone of Widder beds), Thedford,
Ontario; "D" ambulacral view ( X6.4)
31
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