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E CHINODEKMATA.] UPPER PAL/EOZOIC RADIATA. 117 Poteriocrinus NuciFORMis (M c Coy). PI. 3. D. fig. 4. Ref.—M c Coy. Ann. Nat. Hist. 2nd Series, Vol. II. p. 245. Sp. Ch.—Body subovate, pointed below, contracted above from the upper margins of the 1st secondary radials (scapulae) being narrower than their lower portion; pelvic plates long, pentagonal, very narrow below, giving a pointed appearance to the lower portion of the cup ; primary radials large, tumid, subhexagonal, nearly twice the length of the pelvic plates, a little less wide than long ; 1st secondary radials or scapulas pentagonal, about one-third wider below than above, giving a very perceptibly constricted appearance to the upper part of the cup; articulations for the free rays or 2nd secondary radials extending the whole width of the 1st secondary radials or scapulae; irregular 1st interradial large, subhexagonal, supporting two small pentagonal 2nd inter- radials; surface smooth. Length of cup eight lines, greatest diameter (at middle of primary radials) seven lines. This closely resembles the P. Bochschii figured by Geinitz in his ‘ Grundriss der Versteinerungskunde,’ t. 23. f. 13, but of which no description or definition have been published. Position and Locality.—Not uncommon in the carboniferous limestone of Derbyshire. Explanation of Figures.—Plate 3. D. figs. 4, and 4 a different profile views of one specimen, natural size. Genus. CUPRESSOCRINUS {Gold.) Gen. Char.—Column round or four sided, with a crucial alimentary canal; cup broad, shallow; pelvis pentagonal of five pentagonal joints, supporting five large pentagonal primary radials; alternating above which are five very wide and thick secondary radials or scapula; completing the cup; the arm articulation and articular ridge extend the entire width of the scapula; or 1st secondary radials; arms five, as wide as the scapula;, rapidly tapering to an obtuse point, (not divided into hands or fingers) formed solely of plates of the secondary radial series. We might add to the above description, that between one pair of the 1st secondary radials or scapula; are three small interradial plates, not noticed by Goldfuss, but which I have observed in an authentic specimen from the Eifel of one of his species, and which tend to approximate the genus to Poteriocrinus, from which it differs in the very wide shallow form of the cup, and broad undivided rays. CUPRESSOCRINUS CALYX (M r Coy). PI. 3. D. fig. 1. Ref—M'Coy, Ann. Nat. Hist. 2nd Series, Yol. II. p. 244. Sp. Ch.—Cup very wide, evenly convex, saucer-shaped, three times wider than long; pelvis small, slightly concave, pentagonal, of five pentagonal pieces; alternating with and above which are five large primary radials, their length and width equal to the diameter of the pelvis, four pentagonal, and one with a very short sixth lateral side; alternating with and above these, are five pentagonal 1st secondary radials (scapulas), as long as the primary radials, but the width double the length; to the short side of the hexagonal 1 st primary radial is obliquely attached a long pentagonal interradial supporting two very small 2nd interradial plates; scapulas or 1st secondary radials very thick, articular surface flat with an articular ridge running its whole width; all the plates slightly convex and smooth. Width of cup nine lines. Position and Locality.—Rare in the carboniferous limestone of Derbyshire. Explanation of Figures.—PI. 3. D. fig. 1, basal view of specimen natural size.—Fig 1 a profile of ditto. Cupressocrinus impressus (iWCoy). PI. 3. D. fig. 2. Ref.—M°Ooy, Ann. Nat. Hist. 2nd Series, Vol. II. p. 244. Sp. Ch.—Cup four times wider than deep ; pelvis concealed in a deep circular pit, out of which spring the broad ends of five ovate-lanceolate primary radials, the apex of one of which is truncated to support a small elongate interradial plate, and on its side rests a somewhat larger 1st interradial plate; 1st secondary radials (or scapulas) about one-third wider than long, pentagonal, the two lower sides concave, and the lower angles very much prolonged to fit between the lanceolate primary radials; substance of the joints very thick, projecting far
