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Echinodermata.] LOWER PALAEOZOIC RADIATA. 53 in Platycrinus and the next, or cuneiform plate, he here calls scapula, although having nothing in common with the plates so called in the former genus (agreeing rather with its last or cuneiform arm-joint), and so of the succeeding plates; the same confusion exists among succeeding writers to as great an extent, and in various genera. According to the plan here proposed, the scapulae in the one case, and true 1st costal in the other, would equally be called 1st primary radial, and the irregular one of Actinocrinus, the 1st interradial, and the 1st cuneiform arm-joint in one, and the scapida in the other, would be designated by its number, as the cuneiform or last of the primary radial plates in each case. The cup should, in the descriptions, be defined as composed of so many rows of each series (each series being supposed to terminate at a pointed, or cuneiform, joint) and so many rows of inter-radials, the proper numerals being prefixed to each. Genus. TAXOCRINUS {Phill.) = Isocrims (Phill. not of Y. Meyer) = Cladocrinus (Aust. not Agassiz). Gen. Char.—Column and alimentary canal round or pentagonal, cup formed of pelvis, 1st and 2nd primary radials and five 1st interradials; pelvis of five pentagonal pieces, alternating above which, are five large pentagonal (or slightly heptagonal) 1st primary radials (or scapula:) ; remainder of the primary radials, nearly equalling the first in width; five hexagonal interradial plates intervene between the second primary radials, resting on the upper lateral edges of the 1st ditto. The interradial plates and the separation of the primary radial rows seem to separate this genus from Ichthyocrinus. Taxocrinus? Orbignii (M c Coy). PI. 1. D. fig. 1. Ref.—M°Coy, Ann. Nat. Hist. 2nd Series, Yol. VI. p. 28!). Sp. Ch.—Column cylindrical, about two lines in diameter at an inch from the pelvis, and not varying materially in character within two inches from the pelvis; joints finely granulated, uniformly two in the space of one line; pentagonal pelvic plates one line high, alternating with which are the pentagonal or obscurely heptagonal 1st primary radial joints, (or scapulae) nearly one and one-third lines long; arms of two quadrangular and one cuneiform (2nd, 3rd, and 4th primary radial) joints, each one line long, and one and a third lines wide, the latter giving off two rows of secondary radials, (or hands) of five joints, the last being cuneiform, and giving origin to two fingers; from pelvis to end of fingers one inch three lines. I have not distinctly made out the interradial plates, but as there seems a notch between the upper adjacent edges of the first primary radials or scapula:, I have little doubt they existed; besides their presence, the species is easily distinguished from the Ichthyocrinus pyriformis (Phill. Sp.) by the greater number of joints in the arms and hands, and the much thicker column, and the nearly unvarying character of the joints, as they approach the pelvis. Position and Locality.—In the “Asterias” bed of the Upper Ludlow rock at High Thorns, Under barrow, Kendal, Westmoreland. Explanation of Figures PI. 1. D. fig. 1. Body, rays and part of column, natural size from High Thorns, Underbarrow. Taxocrinus tuberculatus {Mill. Sp.) Ref. and Syn.— Cyathocrinus tuberculatus (Mill.) Crin. Sp. Ch.—Arms of two primary radial joints equalling the 1st ditto (or scapula') in size; hands of three secondary radial joints, fingers of five or six joints to the first cuneiform joint, from which they dichotomise once; all the plates coarsely tuberculated; column round of thin joints near the pelvis, becoming thicker and alternately larger and smaller at a little distance; from pelvis to top of first cunei form joint (at end of primary radials or arm) six lines, width of arm two lines, length of hand and fingers about one inch. Position and Locality.—Common in the Wenlock limestone of Dudley, Staffordshire.