RHODOCRINID®. 263 
at the other by an interdistichal. The first plate of the anal side, which 
touches the basals, is larger, and is generally followed by three plates in the 
second row. Column round; composed near the calyx of moderately high, 
thicker, and thinner joints. 
Horizon and Locality. — Niagara group ; Lockport, N. Y. 
Types in the American Museum of Natural History at New York. 
Lyriocrinus melissa (Hatt). 
Plate XI. Figs. 4a, 6, ¢, d, e, f. 
1863. Rhodocrinus melissa — Haut; Trans. Albany Inst., p. 198 (Abstr., p. 4). 
1879. Rhodocrinus (Lyriocrinus) melissa — Hau; 28th Rep. N. Y. State Mus. Nat. Hist. (Mus. edit.), p. 
139, Plate 15, Figs. 18-27. 
1881. Lyriocrinus melissa —W. and Sp. ; Revision Paleocr. Part II., p. 205. 
Calyx depressed, nearly twice as wide as high, distinctly flattened to the 
top of the radials, then curving rapidly upwards until the sides of the upper 
part are at right angles to the truncated lower part. Basal portions forming 
a deep pit, which is surrounded by a pentangular rim, interradially arranged, 
and having a triangular node at each angle. Surface of plates flat, smooth 
or finely corrugated. 
Infrabasals very small, concealed by the column. Basals elongate, gener- 
ally truncated at the upper face, the lower half of the plates curved inward, 
forming the sides of the concavity, the upper half horizontal. Radials large, 
wider than high. Both costals hexagonal, the axillary one smaller, its upper 
angle truncated, supporting a small interdistichal ; the sloping faces support 
2x2 large distichals, which are followed by free arm plates of the same 
order. Arms ten, equidistant; they are stout, long, tapering, and composed 
of short pentagonal pieces ; their pinnules long and closely arranged. Inter- 
brachials: 1, 2, 1, 1; the first as large or larger than the radials, resting 
against the truncate upper faces of the basals. Anal side generally not dis- 
tinct; but it has exceptionally a small additional plate in the second row. 
Ventral disk almost flat, barely rising above the dorsal cup. Interambu- 
lacral spaces slightly depressed ; orals well developed, twice as large as any 
of the other disk plates, and more convex. Anus subcentral, very wide, and 
apparently connected with a tube. Column uniformly cylindrical, the edges 
of the nodal joints marked by a continuous row of small nodes. 
Horizon and Locality. —Niagara group ; Waldron and Hartsville, Ind. 
Types in the American Museum of Natural History, New York. 
