MELOCRINID®. 295 
Melocrinus nobilissimus (Hatz). 
Plate XXIII. Figs. 1a, 2, 3. 
1859. Muriacrinus nobilissimus — Hatt; Paleont. N. Y., Vol. IIL, p. 105, Plate 2, Figs. 1-4, and Plate 
2A, Fig. 1. 
1881. Melocrinus nobilissimus — W. and Sr.; Revision Paleoer., Part II., p. 122. 
A rather large species. Dorsal cup higher than wide, obconical, obtusely 
pentangular above the costals owing to a depression in the upper portions 
of the interradial spaces. The tubular appendages supporting the arms con- 
sisting of two contiguous trunks, which are composed dorsally of two rows of 
plates. Plates marked with obscure radiating ridges; the suture lines well 
defined, with a shallow pit at each angle. 
Basals wider than long, formed into a small subcylindrical cup, not pro- 
jecting beyond the column. Radials larger than the costals, about as wide 
as long. The second costals with an obtuse angle above. Distichals 3 x 10, 
about half the size of the costals, the upper ones axillary and supporting 
upon their outer sloping faces a lateral arm, of which the four or five proxi- 
mal plates, which are longer, are incorporated into the calyx; while the inner 
sloping faces are followed by a row of from six to seven palmars. The latter 
form a vertical line with the distichals, and the plates of adjoining divisions 
are connected laterally, except the two proximal ones of each side, between 
which are interposed small irregular interdistichals. The fourth and fifth 
orders of brachials consist of five plates, the sixth and all orders to the ninth 
of four, the succeeding ones of three, and those near the top of but two 
pieces. The brachials are arranged longitudinally, and connected suturally 
with those of the opposite branch, so as to form a compound, free tubular 
appendage, from which the arms are given off at opposite sides, the axillaries 
supporting on their longer sides the next order of brachials, and on their 
shorter ones an arm. There are about thirty arms to each side of the ray, 
rising to the same general height; all composed from the second plate up of 
two series of interlocking pieces, and all pinnule-bearing. Regular inter- 
radial spaces narrow but long; the first plate rests within a deep notch 
between two radials, and is somewhat larger than the others; the succeeding 
ones are not arranged in horizontal rows, but alternate with one another ; 
they are hexagonal, and the upper lateral faces of the one plate rest against 
the lower lateral faces of the other, thus forming two longitudinal rows side 
by side, each composed of about twelve plates, which decrease in size 
