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62 THE UNIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS
DEVONOBLASTUS LEDA (Hall)
Plate 24, figures 1-2, 6
Pentrenntes leda HALL, 1862, p. 149, pl. 1, fig. 11.
Devonoblastus leda REIMANN, 1935, p. 31.
Description.—A detailed description of the syntypes
has been submitted for publication in another work. The
syntypes are not well preserved and most of the generic
information is taken from the description of specimens
of Devonoblastus whiteavesi. The syntypes are figured on
Plate 24. This species differs from D. whiteavesi in that
the maximum width (or periphery) of D. leda is low,
at or near the radial lips, in contrast to its higher, more
median position in D. whiteavesi.
Occurrence.—Devonian, Hamilton Shale, western
New York.
Types.—Syntypes, 451 (figures 1, 6), and 452 (figure
2), two specimens, Hall collection, New York State Museum,
Albany, New York.
DEVONOBLASTUS WHITEAVESI Reimann
Plate 24, figures 3-5; plate 25, figures 1-12; text-figs. 101-112
Devonoblastus whiteavesi REIMANN, 1935, p. 32, pl. 1, fig. 8.
Granatocrinus leda WHITEAVES, 1889, p. 108, pl. 14, fig. 14.
Description.—The description is mainly on specimen
35,036, supplemented by information from other specimens.
The calyx is calcitic, oval in side view, with short
conical pelvis, 16 mm. long by 10.5 mm. wide, pentagonal
in top view, with periphery near mid-height, and vault
14 mm. long, pelvis 2 mm. long, pelvic angle on basais
85 degrees and on radial bodies 130 degrees. The stem
is round, crenellar, 1.5 mm. in diameter, with approximately
45 crenellae extending inward radially from the
margin one-third of the distance to the small round
lumen. The stem is attached to the basal circlet, which
has a hexagonal raised area at the aboral ends of the basal
plates. Basal circlet pentagonal in aboral view, widely
conical in side view, 2 mm. long by 5 mm. wide, with
strongly rounded medial ridge on each basal. Radials five,
elongate hexagonal, each 14.5 mm. long by 5.5 mm.
wide, with long, narrow, shallow sinus 13 mm. long by
2 mm. wide; radials overlapping deltoids. The surfaces
of the radials and basais are ornamented by fine growth
striae parallel to plate margins.
Deltoids four, lancet-shaped, each 3.5 mm. long by
2 mm. wide, visible in side view, with one large oval
spiracle notched in the adorai end of each, separating the
deltoid into two parts, the deltoid lip located adjacent to
the oral opening and the deltoid body adjacent to the
radial limbs. The surfaces of the deltoid bodies are ornamented
by coarse growth ridges parallel to plate margins,
especially parallel to the radiodeltoid sutures. On the anal
side four anal deltoid plates seem to be present. The small
pentagonal superdeltoid is adjacent to the oral opening
and forms the external border on the adorai part of the
large oval anispiracle. Internally the two cryptodeltoids
rest on the aboral face of the superdeltoid and separate
the anal opening from the adjacent hydrospire canals.
The cryptodeltoids are infolded to form hydrospires on
the anal side, and are overlapped by the radial limbs. The
cryptodeltoids are covered externally by the hypodeltoid
plate and are not visible from the exterior. The pentagonal
hypodeltoid is visible in side view and is homologous
with the deltoid body of each of the other four deltoids.
Five hydrospire folds are seen on each side of an
ambulacrum.
Ambulacra five, linear, slightly recurved below periphery,
each 16 mm. long by 2 mm. wide, with lancet covered
by side plates except at the adorai end, 24 side plates
in a space of 10 mm. along an ambulacrum. The side
plates are normally disposed, with four main cover-plate
lobes to each side plate along the main food groove. A
single large pore is observed between adjacent side plates
along the radial ambulacral margins, and one or two
pores occur along the deltoid ambulacral margins just
above the radiodeltoid sutures. Each spiracle is bordered
by a deltoid lip, two lancet stipes, two side plates, and a
deltoid body.
Occurrence.—Middle Devonian, coral zone of Widder
beds, Hungry Hollow Formation, Thedford and Arkona
areas, Ontario. Shale layer of Tichenor Limestone, Cazenovia
Creek, Springbrook, Erie County, New York.
Types.—Topotype, 35,036, one specimen, Charles
Southworth collection, from Ausable River valley, 2.5
miles northeast of Arkona; University of Michigan, Ann
Arbor. Plesiotype, 34,467, one specimen, from tile yard
0.5 mile north of Thedford, Ontario, Charles Southworth
collection (June, 1954), University of Michigan. Plesiotypes,
E13,065, three specimens, Charles Southworth collection
(1941), from area near Thedford, Ontario, Buffalo
Society of Natural Sciences, Buffalo, New York. Hypotype,
3,661, one specimen, from Thedford area, described
by WHITEAVES (1889) as Granatocrinus leda, Geological
Survey of Canada, Ottawa, Ontario, Canada. Plesiotypes,
S4,648, two specimens, Springer collection, from Ausable
River valley, 2 miles east of Arkona, Ontario, collected
by Charles Southworth; S4,144, one specimen, Springer
collection, from Marsh's Mill, Arkona, Ontario, lower
Widder beds; and 142,025, one specimen, labelled Devonoblastus
leda, Tichenor Limestone, New York, all in
U. S. National Museum, Washington.
Genus DEPLOBLASTUS Fay, n. gen.
Type-spedes, by original designation (herein).—Granatocrinus glaber
MEEK & WORTHEN, 1869.
Generic diagnosis.—Spiraculate blastoids with five
paired spiracles, or four paired spiracles in addition to
a paired anispiracle, with superdeltoid, two cryptodeltoids,
and hypodeltoid on anal side; two hydrospire
folds on each side of an ambulacrum; lancet covered