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Genus STRIATOPORA.-(Hall.)

Fig. 1.

Fig. 2.

Fig. 3.

Fig. 4.

Fig. 1. Striatopora Linneana. Figs. 2, 3, 4. Trachypora elegantula.-Fig. 4 is a portion enlarged: the upper figure a

longitudinal section.

Generic characters.—“Ramose, coralla solid; stems composed of angular cells; apertures of cells opening upon the surface into ex. panded angular cup-like depressions ; interior of the cell rayed or striated, striæ extending beyond the aperture of the cell.”—(HALL. Palæontology of New York, vol. 2, page 156.)

STRIATOPORA LINNEANA.-N. Sp. Description.Stems two or three lines in diameter, branching at an angle of from 75° to 80° ; cells variable in size, the greater number with the expanded mouth one line wide, and the circular cavity at the bottom from one-third to one-half of a line ; the smaller or younger cells, of all sizes, are somewhat uniformly distributed among the larger. In the perfect specimens the mouths of the cells are everywhere in contact with each other, the edges of the walls between them sharp, and the form more or less polygonal, generally five or six sided. In worn specimens the cells are more nearly circular, and the walls obtusely rounded on the edge. The striæ in the cell mouths not observed. I have seen only two specimens of this species, and am unable, therefore, to state to what extent the stems may vary in thickness. In S. rugosa (Hall), * Hamilton Group, Iowa, the cells are distant from each other nearly their own diameter, and the stem is branched at an angle of about 55° (in the specimen figured). In 8. flexuosa (Hall),+ Niagara Group, the cells are, upon an average, more than one line and a half wide, and many of them two lines. Our species, therefore, must be regarded as distinct from either.

Geology of Iowa. Vol. 1, Part 2, page 479, Pl. 1, fig. 6. Palæontology of New York. Vol. 2, page 156, pl. 40 B, fig. la.

seen.

Locality and formation.— Township of Bosanquet, lot 25, con. 5. Shales of the Hamilton Group. Collectors.-A. Murray, J. Richardson.

STRIATOPORA FORMOSA.-N. Sp. Description. -Stems from one line and a half to three lines in thickness ; cells of an uniform size or very nearly so, three-fourths of a line in width, opening out on the surface at an angle of about 45° with the longitudinal axis of the stem, the cell mouths very gradually expanded, apparently fifteen fine obscure striæ occupying the whole surface of the upper lip.

This species differs from S. Linneana in having the cells smaller and of an uniform size. The cell mouths are as wide in stems, one and a half lines in thickness, as they are in the largest specimens

I have not ascertained the angle at which the stems bifurcate. In perfect specimens, where the cells are empty, on looking into them obliquely downwards, they are seen to become circular just below the edge of the lower lip, their diameter there being a little less than half the transverse width of the mouth.

Locality and formation.-Corniferous Limestone, near Woodstock. Collector.-A. Murray.

Genus TRACHYPORA:-(Edwards and Haime.) Generic characters.--"Corallum dendroid, the branches presenting calyces which are only slightly salient, and in which there are no radiating septa ; cænenchyme very abundant, solid, and with the surface marked by strong, irregular, vermicular, and sub-echinulated striæ." -(EDWARDS and HAIME. Polypiers Fossiles des Terrains Palæozoiques. Page 305.)

The only species of this genus heretofore known, is T. Davidsoni (E. and H.), which occurs in the Devonian Rocks at Ferques, in France.

TRACHYPORA ELEGANTULA.-N. Sp.

(See Figs. 2, 3, 4.) Description.-Stems (in the specimens examined) from two to two and a half lines in diameter, branching at an angle of about 75°.

lls arranged in four or five rows, parallel with the axis of the stem ; they are oval, about one line in length and two-thirds of a line wide, with an elevated margin at the sides, in general effuse above, rarely

effuse below. The space between the cells is marked with irregular, flexuous, broken striæ, four or five in the width of one line; the elevated margin at the sides of the cells exhibits from seven to nine short oblique ridges or tubercles. In the longitudinal rows, the cells are sometimes in contact with each other, and often separated by distances equal to half their own length, or a little more. In T. Davidsoni, the cells are not arranged in linear series, and the striæ are of a different form.

Locality and formation.-Lot 25, con. 5, Bosanquet.
Collectors.-A. Murray and J. Richardson.

Genus ALVEOLITES.-(Lamarck.)

The following three species appear to belong to this genus :

ALVEOLITES ROEMERI.--N. Sp. Description.-Stems from two to three lines in diameter, usually cylindrical, but sometimes sub-palmate, branching. Cells transversely oval, about half a line wide and one-fourth of a line in length; in general distant from each other from half a line to two-thirds of a line in the longitudinal direction of the stem, and half that distance in the transverse direction.

In some specimens the cells are not quite so distant as above stated, and it may be that these should constitute a distinct species. In A. labiosa (Canadian Journal, March, 1859), the cells, when perfect, are scarcely one-fourth of a line wide; A. cryptodens (Loc cit), is, upon the whole, a larger species, with the cells about a line distant.

The stems appear to bifurcate at an angle of from 50° to 60°; but the specimens are not sufficiently perfect to determine this character with certainty.

Locality and formation.-Lot 25, con. 5, Bosanquet. Hamilton Shales.

Collectors.-A. Murray, J. Richardson.

ALVEOLITES GOLDFUSSI.-N. Sp. Description.—This species occurs in irregularly circular depressed masses, several inches wide and one or two inches in height. The corallites radiate from a point in the bottom, and the mass, rapidly increasing in width, has a very obtusely turbinate form, flattened and undulated on the top, and apparently composed of horizontal super

imposed layers. The cells are transversely sub-oval or sub-triangular, usually with one curved side and two straight sides. In some parts of the mass, especially on the edges, they approach the sub-circular polygonal form, but usually they are wider in the one direction than in the other. The width is in general three-fourths of a line (sometimes one line), and the height half a line. The bottom of the mass is either in part or wholly covered by a thin, smooth, but concentrically undulated epitheca.

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Fig. 5. Alveolites Goldfussi.— Upper side of a small specimen.

Fig. 6. Alveolites Fischeri.-One side of a frond. This species resembles A. suborbicularis (Lamarck) of the Devonian Rocks of England, France, and Germany; but in that species there is a groove on one side of the cell, and a corresponding ridge on the side opposite. I have not been able to detect these characters in very well preserved specimens of A. Goldfussi, and feel satisfied that it is therefore a distinct species.

Locality and formation.-Lot 25, con. 5, Bosanquet. Hamilton Shales. Collectors.-A Murray, J. Richardson.

ALVEOLITES FISCHERI.-N. Sp.

(See Fig. 6.) Description. This species is found in the shape of flattened, palmate, obscurely branching fronds, celluliferous on both sides. Some of the fragments appear to be portions of undulated expansions, two to four lines in thickness, and several inches wide. The majority of the specimens, however, indicate a palmated form, two to four inches in length, from half an inch to more than one inch wide, and from one to three lines in thickness. The cells, when perfect, are transversely sub-oval or sub-triangular, usually with one curved and two straight sides, from half a line to two-thirds of a line wide; distant from each other about two-thirds of a line in the vertical, and a little less in the transverse direction of the frond. When well preserved, the lower lip, or edge of the cell, is thin, sharp, and uniformly arched. In the very thin fronds (one line in thickness), the cells open out on the surface at a very acute angle, apparently 15° to 20° ; but in the thicker specimens the angle is greater-sometimes 45o.

Locality and formation.-Bosanquet. Shales of the Hamilton Group.

Collectors.--A. Murray, J. Richardson.

ALVEOLITES SQUAMOSA.—N. Sp. Description. This species is found in wide, flat, irregular expansions, sometimes six or seven inches in breadth, and from half an inch to one inch and a half in thickness ; composed of successive, and often much distorted, layers; the cells opening out upon the surface very obliquely, and separated from each other by exceedingly thin partitions, which, when silicified and well brought out by the action of the weather, present a peculiarly rough squamose appearance. The cells are linear, in general about half a line in length, and apparently one-tenth of a line in width. One of the specimens examined exhibits two spots, one-fourth of an inch wide each, where the cells are less than half the average size. There are obscure indications of a central ridge on one side of the cell in this species, as there is in A. suborbicularis.

This species differs from A. Goldfussi in having much smaller and more compressed cells. In a space one-fourth of an inch square, I have counted ninety-seven cells; and the average appears to be from seventy-five to one hundred, with here and there spots holding double that number. In A. Goldfussi there are from sixteen to thirty in the same area. On comparing the figures of A. suborbicularis in the works of GOLDFUSS, SANDBERGER, and BRONN, it will be seen that in that species there are about fifty cells in one-fourth of an inch square. The difference in the size (great though it be) might not be sufficient to separate these three species, but the form of the cells appears to be also different. A. Goldfussi has not the groove on the

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