—— 
418 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Dizygocrinus facetus (Mitter and Gurtey). 
Plate XX XIT, Fig. 12. 
1890. Batocrinus facetus — MILLER and Guriny; Journ. Cincin. Soc. Nat. Hist., Vol. XIII. (Authors’ 
copy, p. 35), Plate 6, Fig. 8. 
Calyx below medium size, wider than high; in ornamentation and gen- 
eral appearance resembling D. wdianensis, but having less than half the num- 
ber of arms. Dorsal cup semiglobose ; the radial plates marked by narrow 
ridges, which follow the median portions of the plates. Plates convex, 
covered with irregular stris and small nodes. Suture lines grooved and 
rather distinct. 
Base very short, circular, almost resembling a stem joint. Radials short, 
nearly twice as wide as long; the upper face concave. First costals com- 
paratively large, quadrangular, as long as the radials but considerably nar- 
rower; their upper and lower faces convex. Second costals a little wider 
but not longer than the first; heptagonal ; the upper faces obtusely angular. 
Distichals varying in number; the anterior ray having three rows, which 
support the arms; the antero-lateral ones but two, followed by two fixed 
palmars. In the two posterior rays, the axillary costal supports upon the 
side facing the anal interradius two rows of distichals followed by 2 X 2 pal- 
mars, upon the opposite side three distichals. Arm formula: 3. Arm bases 
projecting, directed obliquely upward, and separated interradially by small 
interbrachial pieces, which connect with the plates of the ventral disk. 
Arms single, long, decidedly tapering until quite slender at the tips; com- 
posed from the third joint up of two series of rather long joints. Pin- 
nules extremely long, stout, cylindrical, formed of ten to twelve joints, 
which are about four times as long as wide. Interradials: 1, 2,/1, and 
one or two irregular pieces in the arm regions. Anal plate as large as the 
radials, supporting 8, 8, 2, and 1 plate. Ventral disk depressed conical, 
the plates tumid and of regular size; anal tube slender but comparatively 
long, composed of nearly flat pieces, among which at intervals others are 
interposed bearing sharp tubercles. Column round; the nodal joints with 
rounded, strongly projecting edges. 
Hlorizon and Locality. — Keokuk group ; Canton, Ind. 
fiemarks. —This species was described as having seventeen arms, which 
is abnormal, the regular number being sixteen. Neither has it “ eleven anal 
plates.” The authors evidently mistook the lateral ends of the arm-bearing 
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