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to the diameter of one inch and a half at a length of two inches and a half. Cup about three-fourths of an inch in depth, the form of the bottom variable, either with a smooth space or a small pit in the centre, or covered with the prolonged radiating septa; these latter about one hundred and fifty in number; the interseptal spaces filled for a short distance from the outer surface with small sub-lenticular cells, of which there are about four in one line; a small space beneath the bottom of the cup in full-grown specimens, with flexuous transverse diaphragms. Surface, when perfect, with sometimes a few inconspicuous encircling annulations of growth, but often with a somewhat smooth aspect, longitudinally marked with the septal striæ, of which there are, on an average, five or six in the width of two lines; when partially decorticated, the interseptal spaces roughened with small subimbricating projections or notches, with their sharper edges usually turned upwards-about four of these in one line. The largest specimen that I have seen is three inches and one-fourth in length, measured along the surface of the side with the larger or convex curve, and one inch and a half on the lesser curve. The diameter of the cup, in the same specimen, is one inch and a half. Several others that I have seen are from one to two inches and a half in length.
The arrangement of the septa in the bottom of the cup appears to vary a good deal in different individuals. In one specimen two inches in length, there is a deep septal fossette on one side, and a pit in the centre of the cup. The septa branch off, as it were, on each side of a depressed line, extending from the central pit to the fossette. In another, about the same size, the septa all reach the centre in the bottom of the cup, and are there somewhat twisted to. gether. There is a septal fossette in this specimen also. In a third individual, with a cup one inch in diameter, there is a smooth space two lines wide in the centre, with an obscurely indicated septal fossette. I think it probable that most of the large individuals will be found to have the bottom smooth.
The form of the walls of the cup also varies according to the age of the individual. In the immature it is thin, and the septa alternate somewhat in size. But in the large ones (three inches in length) the interseptal spaces are filled with the cellular tissue nearly to the free edges of the septa, and the wall of the cup is thus rendered solid for the thickness of two lines, or a little more.
In those large ones, also, it is to be observed that the septa are of a nearly uniform size when seen in the upper part of the wall of
There are several species of fossil corals in the Corniferous Limestone, which resemble this one in external appearance :
1. Zaphrentis prolifica.— The greater number of the specimens are about the same size as those of C. Zenkeri, but are more slender towards the base, seldom uniformly curved, the septa alternating in size in the walls of the cup, and the septal striæ four in two lines. The worn specimens do not exhibit the roughened nodulose exterior presented by C. Zenkeri when partially decorticated.
2. Cyathophyllum Lesueuri. This is a somewhat larger species, with the septa (just within the margin of the cup) distant nearly one line from each other, but with the septal striæ as closely arranged as they are in C. Zenkeri; and further, under certain conditions, exhibiting ten striæ to two lines.
3. Zaphrentis cornicula.--(Edwards & Haime.) This species has not been found to my knowledge in Canada, but I have before me two specimens from Ohio (from Dr. Shumard.) The surface resembles C. Zenkeri, but then the septa inside of the cup are denticulated on their edges and, besides, are large and small alternately. Z. cornicula appears to be a Heliophyllum.
4. Clisiophyllum Oneidaense.—The perfect specimens are marked with numerous sharp annulations, but when the outer surface has been worn away, the interseptal spaces exhibit either transverse diaphragms, nearly a line distant from each other, and turned upwards, or small projections similar to those of C. Zenkeri, but two or three times more distant.
Locality and formation. - Rama's Farm, near Port Colborne. Collector.-E. Billings.
CHONOPHYLLUM MAGNIFICUM.-N. Sp.
(See Plate I.) Description.-Short, turbinate, expanding to the width of six or seven inches at a height of four inches and a half; upper surface constituting a nearly flat circular disc, with a rounded cavity in the middle, one inch and a half wide, from which radiate one hundred and twenty-five depressed convex ridges; the grooves between them
narrow, and somewhat angular in the bottom.
These ridges are gently curved in crossing the broad flat margin of the cup. The depth of the central cavity is about one inch. A transverse or hori. zontal section shews that many of the septa (probably one-half of them) reach the centre. In a vertical section, extending downwards, so as to cut off the outer extremities of a few of the radiating ridges, it is shewn that the grooves on the floor of the cup indicate the position of the septa, and that the ridges are the interseptal spaces. The structure, as exhibited in this section, consists of excessively thin, parallel, horizontal laminæ (apparently from thirty to forty in the thickness of one line.) These laminæ are arched upwards between the septa, the curve corresponding with the convexity of the radiating ridges. In the lower part of the corallite, the interseptal tissue is much coarser. The surfaces of the ran diating ridges appear to be covered with small tubercles.
(See Pl. I. 6.)
The only specimen of this truly magnificent coral that I have seen, is imbedded in an upright position in the rock, the broad circular disc of the cup (with the greater number of the rays well exposed by the action of the weather) being just on a level with the surface of the stratum. The width of the disc or cup in this individual is six and a half inches ; and it exhibits one hundred and twenty-five radiating ridges, which attain a breadth of about two lines at the margin. It is highly probable that in other specimens the number of rays may be a little less or greater than it is in this one. The thickness of the piece of rock in which it is imbedded is three inches ; and on the under surface a transverse section of the coral is exhibited, with a diameter of one inch and a half, and consequently it expands from that size to a width of more than six inches in the length of three inches. At this rate of tapering, the total length of the perfect fossil must be about four inches and a half. Most probably a small portion of the pointed base is more or less. curved. I have not seen the surface below the edge of the disc.
This species resembles Chonophyllum perfoliatum (Goldfuss), but; is much larger, and has double the number of radiating septa.
Locality and formation.-Lot No. 1, con. 14, Township of Walpole.
Collector.-J. De Cew.
Genus LINGULA.-(Bruguière.) Of this genus, only one species has been found in the Devonian rocks of Canada West. The specimens are too imperfect for description.
STREPTORHYNCUS PANDORA.-N. Sp.
Description.-Shell semioval, or sub-quadrate ; length about threefourths the width, hinge line equal to the greatest width of the shell, sometimes a little less, usually forming a right angle with the sides of the cardinal extremities ; front margin broadly rounded. Ventral valve depressed semiconical, most elevated at the beak, thence descending with a slightly concave or nearly flat slope in all directions, to the margin. Area of ventral valve, large triangular, extending the whole length of the hinge line, sloping outwards at an angle of about 100°, with the plane of the lateral margin ; foramen triangular, very conspicuous, its width at base nearly twice the height, nearly or altogether closed by a convex deltidium. Dorsal valve moderately convex, gently compressed towards the cardinal angles. Surface with very narrow, strongly elevated, radiating ridges, of which there are from four to six in the width of one line ; the increase appears to be both by bifurcation and interstitial addition, the latter mode being the most common.
Width of a specimen of medium size, sixteen lines ; length of same, from the beak of the ventral valve to the front margin, twelve lines ; height of area of ventral valve at the beak, two lines and threefourths ; width of foramen at base, four lines and a half. Another specimen is twenty lines wide and sixteen in length. Besides these,
there are other imperfect specimens from two inches to two inches and a half in width, which I have no doubt belong to the species.
The inclination of the area of the ventral valve, judging from several fragments that I have examined, appears to vary considerably.
This species belongs to that group of the genus of which 0. umbraculum (Schlotheim) is a characteristic form. Mr. Davidson has recently placed the species of this type in the gems Streptorhyucus (King) with the following remark : "The shells composing this sub-genus, are closely related to Strophomena; they are usually semicircular, convex or concavo-convex, and externally striated ; the ventral valve possessing a prolonged and oftentimes bent or twisted beak.”— (GEOLOGIST, March, 1860.) The species vary greatly in size and form, and Mr. Davidson has, therefore, united under one name (S. crenistria) no less than twelve varieties, which have all been considered to be distinct by various authors. Our fossil closely resembles S. crenistria in external form, but differs in not having the radiating striæ crenulated, and further in the form of the occlusor muscular impressions in the dorsal valve. According to Davidson's figure, there is a small process between the two branches of the cardinal process of the dorsal valve, which does not exist in ours. I shall give some further illustrations of this species hereafter. It is only since this article was sent to the press that I have procured specimens which exhibit the interior of both valves.
Locality and formation.-Lot No. 6, Con. 4, Townsend. Also at Rama's farm, near Port Colborne, and near Woodstock. Collectors.—A. Murray, E. Billings and J. De Cew.
Orthis Livia.- N. Sp
Fig. 16. Fig. 14. Orthis Livia.-Ventral valve, Fig. 15,-Longitudinal section of the same.
Fig. 16.-Dorsal valve.