ECHINODERMATA - KU ScholarWorks - University of Kansas

72 THE UNIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS
are seven hydrospire folds on each side of a normal
ambulacrum ("A," "B," "C," "E") and 6 hydrospire
folds on each side of the "D" ambulacrum.
The "D" ambulacrum is 3 mm. long by 3 mm. wide,
the "A" and "B" ambulacra 15 mm. long by 1.25 mm.
wide, and the "C" and "E" ambulacra 17 mm. long by
1.25 mm. wide, the widest part being adjacent to the
deltoids. The lancet plate is covered by side plates, with
22 side plates in a space of 10 mm. along a normal ambulacrum.
The "D" ambulacrum has seven side plates
in all on each side, but these are similar to those of the
other ambulacra except for being more elongate. The
side plates are normally disposed, with one large pore between
adjacent plates along the deltoid and radial margins,
and five cover-plate sockets to each side plate along
the main food groove. The surfaces of the calyx plates are
ornamented with fine growth lines parallel to plate
margins.
Occurrence.—Middle Devonian, Hamilton Group,
Beargrass Creek, Jefferson County, Kentucky (S4,960).
Hamilton Group, Louisville, Kentucky (S4,963). Coral
zone of Widder beds, Hungry Hollow Formation, Thedford,
Ontario (108; 3,665; E13,061; E15,933).
Types.—Neotypes, S4,960 (new holotype); S4,963
(new paratype), old numbers S3,666 and S3,665 respectively,
Springer collection, S4,963 figured by ETHERIDGE
& CARPENTER (1886), pl. 19, fig. 3, U. S. National Museum,
Washington. Plesiotype, 108, one specimen, University
of Illinois, Urbana. Plesiotype, 3,665, Geological
Survey of Canada, Ottawa. Plesiotypes, E13,061, four
fragmentary specimens, Charles Southworth collection
(1941); and E15,933, one specimen, Charles Southworth
collection (1943), Buffalo Society of Natural Sciences,
Buffalo, New York.
Genus ELLIPTICOBLASTUS Fay, 1960
Type-species, by original designation.—Pentatrematites orbicularis
SOWERBY, 1834.
Generic diagnosis.—Spiraculate blastoids with five
spiracles, or four spiracles in addition to an anispiracle,
with superdeltoid, two cryptodeltoids, and a hypodeltoid
on anal side, a hydrospire plate, approximately
twice as many pores as side plates along the deltoid
and radial margins, one long, curved hydrospire fold
on each side of an ambulacrum, radials overlapping
deltoids, lancet exposed along middle one-third of its
width, and calyx shape elliptical. Lower Carboniferous,
England.
Remarks.—The genus Ellipticoblastus was probably
derived from Globoblastus by reduction of the
two hydrospires on each side of an ambulacrum to
one. The lancet plate migrated outward, thus exposing
the middle portion.
ELLIPTICOBLASTUS ORBICULARIS (Sowerby)
Plate 43, figures 7-9, 12; text-fig. 138
Pentatrematites orbicularis SOWERBY, 1834, P. 456, pl. 33, fig. 5.
Ellipticob/astus orbicularis (SOWERBY) FAY, 1960, p. 315-317, pl. 1,
fig. 7.
Description.—Calyx calcitic, flattened globular, 8.5
mm. long by 8 mm. wide, with periphery near mid-height
at radiodeltoid suture. Stem round, crenellar, 1 mm. in
diameter, with small, central, round lumen. Basal circlet
pentagonal in basal view, 3 mm. in diameter, in slight
basal concavity, with three normally disposed basal plates.
Radials five, each pentagonal in side view, extending onehalf
of length of the calyx, with long, narrow, shallow
sinus 5.5 mm. long by 1.25 mm. wide; radials overlapping
deltoids at a high angle. The angle formed along
the radiodeltoid suture, with center at junction of interradial
sutures with radiodeltoid sutures is 95 degrees.
Deltoids four, long, lancet-shaped, each 6 mm. long
by 3.5 mm. wide, each pierced in the adoral tip by one
large oral spiracle. Each spiracle has a steep raised margin
and each wide, short deltoid lip has approximately
seven long cover-plate lobes along the aboral margin. On
the anal side two external anal deltoids are seen, a superdeltoid
and hypodeltoid, with anispiracle between. Anal
opening filled with matrix. It is assumed that two small
cryptodeltoids are present but covered, as seen in other
specimens. One hydrospire fold is present on each side
of an ambulacrum, as in other specimens.
EXPLANATION OF PLATE 21
FIGURE
1-10. Cordyloblastus eifelensis (RoEmER). 1 3. Topotype,
213, Schultze coll., Harvard Mus. Comp. Zoology; Middle
Devonian (Eifelian), Nollenbach, near Kerpen, Germany;
oral, "D" ambulacral, aboral views (all X3.7).
4,5,7. Plesiotype, E21,087, Buffalo Soc. Nat. Sci.; Middle
Devonian, Eifel, Germany; oral, "D" ambulacral, aboral
views of an immature specimen (all X 13.1).-6,8.
Plesiotype, 195, Schultze coll., Harvard Mus. Comp.
Zoology; Middle Devonian, Eifel, Germany; oral and "DE"
PAGE
interambulacral views of an abnormal specimen showing
development of a small sixth radial plate in "DE" interambulacrum
( X 3.8).-9,10. Topotypes, 305, Schultze
coll., Harvard Mus. Comp. Zoology; Middle Devonian
(Eifelian), Nollenbach, near Kerpen, Germany; 9, long.
polished section of an ambulacrum showing hydrospires
( X13); 10, oral view of polished section showing the two
cryptodeltoids (slightly darker calcite) resting on lightercolored
superdeltoid near oral opening and extending aborally
(downward) (X5) 56