Geological Position and Locality. This elegant little crinoid is quite abundant near the top of the cavernous beds of the subcarboniferous limestone, Edmondson County, near the Mammoth Cave. Good specimens are rare. The vertical range of this species, so far as ascertained, is about thirty-eight feet.

Remarks. D. elegans is nearly allied to D. symmetricus and several undetermined species; it will readily be distinguished from D. symmetricus by its more erect figure, the absence of the strong spinous central piece at the summit, by the greater prominence of the arms, as well as the larger number at the body, and the consequent greater number of small pieces making up the clusters about the arm facets.

DICHOCRINUS FICUS, Sp. Nov.

Body. Subovoid, inflated near the centre of the length of the first radial pieces, from which it contracts toward the summit of the calyx; contracting regularly toward the column, around which it is inflated. Columnar pit small, slightly depressed.

Basal pieces two, similar in form and size, obscurely pentagonal; dividing line straight; the summit of the pieces united present five slightly curved depressions, and one angular notch for the reception of the radial and anal pieces.

Radial pieces, first series five, similar in form and size, a little higher than wide, subquadrangular; the upper margin slightly indented near the middle for the reception of the radials of the second series. Radial pieces, second series, five, minute, semicircular, buried in the indentation at the summit of the first radials. Radial pieces, third series, small, depressed, cuneiform, axillary; the oblique upper margins of each support two arms.

Anal piece, — one, similar in form and size to the first radial pieces; like them it bears a second and third radial, and a pair of arms.

Arms. Twelve, composed of rather long, quadrangular pieces, rising from the third radial piece and bifurcating on the second piece above it. Only two ossicula above the bifurcation are preserved on our specimen. The arms are slender.

Vault. Our specimens do not show the vault. It is unknown. Column. Small, near the body, composed of thin pieces of equal size and thickness; the edges are rounded.

Geological position and locality. Rare, in beds at the top of the sandy mud beds at the base of the subcarboniferous limestone, Clear Creek, Hardin County, Kentucky; Montgomery County, Indiana, &c.

DICHOCRINUS SCULPTUS, Sp. Nov.

Body. Short, conical, regularly expanding from the column to the summit of the first radials; the basals and first radials are elaborately ornamented by prominent irregular carinæ, which generally lie nearly parallel to the vertical sides of the pieces.

Basal pieces. Two; similar in form and size, pentagonal; dividing line straight; columnar facet large, prominent, expanded, producing a rim around the column and the margin of the calyx. The joined basal pieces have four curved and two angular depressions at the summit; the deepest and largest of the latter marks the anal side.

Primary radials: first series five; subquadrangular, one third higher than wide, inflated at the junction with the second radials, which rise from a depression in their upper margin. The radials of the second and third series (?) are absent; their form is unknown. Anal piece. One; similar in form and arrangement to the radials of the first series.

Arms.
Column.

The form and number of arms are unknown.
Unknown.

Dimensions:

Height of calyx .

Diameter at summit of first radials

Diameter of inflation at the insertion of the column

Geological position and locality. A single specimen of the calyx was obtained from the first limestone above the base of the millstonegrit beds, in Hardin County, Kentucky.

Remarks. The ornature of this beautiful crinoid will distinguish this from all other known species.

Summit covered by many polymorphous pieces.

Column round, small, formed of alternate large and small

thin pieces.

Radial pieces all arm-bearing.

Anal piece none.

COTYLEDONOCRINUS PENTALOBUS, Sp. Nov.

Body. When the arms are absent the body is a long ovoid figure; the summit contracting rapidly, while the lower portion of the calyx, as high as the top of the basal pieces, is rather more elongated. The base is rounded, and intumescent about the column. The two basal pieces, when united, form a conical cup about as deep as wide, having four slight concave depressions on its upper margin, and one angular notch. The junction of the basals rises between the concave depressions, dividing them into pairs, the angular notch being equally taken from the pieces on either side of the line dividing them. Columnar pit small, the presence of the column in our specimens concealing its depth; it is probably quite shallow.

The first primary radials are large, more than twice as high as wide, a little wider in the middle of the length of the pieces than at the ends. The second and third primary radials are buried in an excavation at the summit of the first radials. There is no gibbosity or swelling at the insertion of the second radials; the first radials appear to run under them perfectly smooth.

Second primary radials five; they are very minute, lunette-formed, less than a semicircle, slightly depressed at their upper margin.

Third primary radials, five; small, leaf-like, resting upon the second radials, spreading beyond them, the outer margin expanding upward. The centre of the pieces is prolonged upward into a little tonguelike figure; on either outer margin is also a prolongation about half as wide as the centre one, and of nearly equal height, leaving a deep, square-like notch on each side of the centre prolongation of the pieces.

First secondary radials. These pieces are ten in number, two to each third primary radial; they are similar in form and size, about as high as wide, fitting into the indentations on either side of the third primary; they rise a little over one third of their height above the centre prolongation of the primary to which they are joined, are truncated obliquely downward and outward from their junction with each other; the outer margins falling into, and further expanding, the somewhat circular outline of the second and third primary radials.

Second secondary radials. Ten in number, resting on the bevelled upper margins of the pieces below them, nearly as high as wide, deeply indented for the reception of the first brachial pieces, thus divided into three tongue-like points, not unlike the centre point of the third primary, and two oblong circular depressions; each division of the upper margin of the pieces occupying about one fifth of its length; they are joined together by a straight line continuous with that marking the junction of the pieces immediately below them.

Arms. Twenty, delicate, three times as long as the calyx, each ray supporting four; they are non-bifurcate, composed of about six thin, irregular, oblong pieces above the first brachial, where they are composed of a double row of very thin pieces, joined in the centre of the arms by angular points, which fit into the alternate depressions on either side, the junction forming a serrated line; each of the pieces. forming the double row composing the arms bears a long filamentous cilia, which is composed of very minute pieces, the length of which is about equal to their diameter.

Inter-radial pieces. Between each group of four arms, and rising in the notch between the first radials, are three, sometimes four, small inter-radial pieces; the first is pentangular, widest below the centre of the inferior margin, angular, the superior margin a horizontal line;

upon this are disposed the other pieces, one above the other, rapidly diminishing to a point.

Summit. The summit is divided into five fields; the division line appears to radiate from the centre of the summit to the centre of each group of arms. Four of these fields are nearly alike; the form and the arrangement of the pieces in each are similar; the fifth field, which lies above the junction of the basal pieces, between the pairs of circular depressions, supports a short rudimentary proboscis near its centre, about .01 of an inch in diameter, and about .15 of an inch in height, composed of a great number of small pieces (seventy to eighty). The pieces covering the fields are of irregular size, the general form inclining to triangular; some are quadrangular, one end of the piece being much narrower than the other; other pieces are elongated octagons.

Column. The column is round, delicate, composed of very thin pieces, the alternate ones larger and smaller; near the calyx the column suddenly enlarges to its insertion into the columnar pit.

Geological position and locality. Rare, in the third limestone above the base of the millstone-grit beds of Grayson Springs, Grayson County. Its vertical range appears to be quite limited.

Remarks. This elegant little crinoid is closely allied to Dichocrinus and Pterotocrinus; it differs from both genera in the number of pieces forming the series resting on the basal pieces. The deepest angular notch in the basis of both genera usually marks the anal side; in our genus the mouth is on the field, on the side directly opposite the only angular notch in the basis. All the pieces rising from the basals bear arms in our genus; but this is also true of DICHOCRINUS FICUS, which has six arm-bearing pieces, and no barren or non-armbearing piece, termed anal piece in this genus.

As genera and species are now defined, we are compelled to sepa