Geological Survey of Ohio
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GEOLOGICAL SURVEY OF OHIO. VOL. 1. PART II. PALÆONTOLOGY. SECTION I. DESCRIPTIONS OF INVERTEBRATE FOSSILS OF THE SILURIAN AND DEVONIAN SYSTEMS. BY F. B. MEEK. Digital version copyrighted ©2012 by Don Chesnut. T O D R . J. S. N EWBERRY , State Geologist: DEAR SIR: In respectfully submitting this Report on some of the Invertebrate fossils of Ohio, I desire to acknowledge here my obligations to the following gentlemen for the loan of numerous fine specimens from the Cincinnati rocks, viz: Messrs. C. B. Dyer, U. P. James, S. A. and Dr. Miller, D. H. Shaffer, and Drs. Hill and Byrnes. To Mr. James and Mr. Dyer, as well as to some of the others, I am likewise indebted for much interesting information in regard to the vertical range, etc., of the species and varieties in the Cincinnati beds. These gentlemen have been collecting the fossils of this exceedingly rich locality for many years past, and now possess extensive and valuable collections, from which they generously allowed me to select any specimens I wanted for study or illustration. Some of those thus borrowed from Mr. Dyer, are types of species described by others, but not hitherto figured. I am also under obligations to the Rev. Mr. H. Hertzer, and Prof. Edward Orton, of the Ohio Survey, for the loan of some interesting Devonian and Upper Silurian fossils, belonging to their own private collections, from near Columbus and Yellow Springs, Ohio. Among parties living out of the State, to whom I am indebted for the loan of specimens for comparison and study, I would mention Prof. C. F. Hartt, of Cornell University, New York; Prof. Oliver Marcy, of Evanston University, Illinois; Prof. Frank H. Bradley, of Knoxville University; Dr. E. Billings, of Montreal, Canada; Dr. I. A. Lapham, of Milwaukee, and Dr. F. H. Day, of Wamatosa, Wisconsin. I am also under special obligations to Prof. Joseph Henry, for important facilities at the Smithsonian Institution, during the preparation of this Report. It is due to myself to remark here, that I have labored under the disadvantage of having to form conclusions in regard to the relations of many Ohio forms to species that have been described by others from this and adjoining States, without having typical or well authenticated examples of the named species for comparison. This difficulty was most particularly felt in the study of the fossils from the Devonian and Upper Silurian beds, from which many species have been described (often very briefly), and either not yet figured at all, or only imperfectly illustrated. Very respectfully yours, F. B. MEEK. S MITHSONIAN INSTITUTION, Washington City, D. C., Feb. 7, 1873. FOSSILS OF THE CINCINNATI GROUP. RADIATA. ECHINODERMATA. CRINOIDEA.* GENUS HETEROCRINUS, Hall, 1847. (Palæont., N. Y., vol. 1, p. 278.) In first publishing this genus, Prof. Hall illustrated it as having only a single range of body pieces below the radial series, and without anal plates or pinnulæ. Species subsequently described by Mr. Billings, and others by the writer and Mr. Worthen, however, show that it has a well-developed anal series, and that the arms are often, though not always, provided with pinnulæ. Still more recently, Prof. Hall (see his Descriptions New Sp. Crinoidea, p. 4, dated 1866) called attention to the presence, in some species of this genus, of five very minute pieces at the connection of the column with the body; one being placed directly at the lower end of each suture dividing the first range of well developed body-plates. These minute pieces he views as true basals, and the range just above them, that have always been regarded as the basals, he considers sub-radials–thus making the genus have both sub-radial and basal pieces. I have some doubts, however, in regard to the propriety of this view of these parts, not only became the minute pieces at the head of the column are sometimes entirely wanting, and never so much develope d * It way be proper to mention here, that some recent investigations of the soft parts of Comatula, by Prof. Metschnikoff, of St. Petersburg, seem to render it very doubtful whether the Crinoidea really belong to the Class Echinodermata at all, as generally believed. At any rate, he could find no traces whatever, in Comatula, of the water system of the Ophiurians, Star-fishes, Echini and Holothurians. (See Bull. Acad., St. Petersburg, XV., p. 508, Feb'y, 1871; and Am. Naturalist, Vol. VI., May, 1872, p. 305.) 2 PALÆONTOLOGY OF OHIO. as to form a contiguous range of pieces all around; but also, because they correspond exactly in size and form, and in their vertical range, with five others often seen intercalated between each two of the discs of the column for some distance below the body. In this, as in some other genera, particularly of Silurian age, the column is always equally divided, longitudinally, into five sections, so that each of its discs is really composed of five distinct pieces, which, however, frequently become anchylosed together. The more minute pieces mentioned above are also always placed exactly at the dividing lines between each two of the five larger ones composing each disc of the column, and thus form rows exactly coincident, vertically, with those at the head of the column. Farther down the column, these minute pieces become more and more extended laterally, until finally they connect with each other, and thus themselves form discs—at first thinner than those with which they alternate, but still farther down the column, they become, in part at least, of the same size as the latter. (See fig. 3 a, pl. 1.) From these facts, I am inclined to think the very minute pieces at the immediate connection of the column with the body, should rather be viewed as belonging to the column, than as true basals. I have, therefore, in describing the species in which these minute pieces exist, always called them sub-basal pieces, and the well developed range above, basals. In the paper above quoted, Prof. Hall, in speaking of these minute sub-basals in this genus, also remarks, that, if they were “developed, the structure would be the same as in Poteriocrinus; and in the absence of these plates, those which are the sub-radials in that genus, become the basal or lower series.” It seems to me, however, that even if these minute pieces in this genus were large enough to assume the character of true basal, the structure of the genus would still be constantly distinct from that of Poteriocrinites, in the number and arrangement of its anal pieces. In Poteriocrinus, the anal pieces always rest directly down upon the sub-radials, and generally consist of two vertical rows of alternating pieces, the lowest piece being often, as it were, wedged down obliquely, partly under the first radial on the right; while in Heterocrinus, there is always but a single row of true anal pieces, the first or lowest one of which, instead of resting down upon the range of pieces that would, according to Prof. Hall's view, correspond to the sub-radial pieces in Poteriocrinus, actually rests upon one of the sloping sides of the second radial on the right, and partly upon the first radial on the left. This structure seems to be constant in all the species, and imparts so singular an appearance to the anal series, that they have generally been mistaken by Prof. Hall for an arm. FOSSILS OF THE CINCINNATI GROUP. 3 HETEROCRINUS CONSTRICTUS, Hall. Plate 1, figs. 10 a, b (and 11 ?). Heterocrinus constrictus, Hall, —; Illustrations of a paper entitled “Descriptions New Sp. Crinoidea,” etc., dated 1866, p1. 1, fig. 3 (without description). Body short sub-cylindrical, or slightly tapering below, and distinctly constricted just below the arm-bases above. Sub-basal pieces wanting, or only appearing as minute, imperfectly developed divisions of the last joint of the column, without modifying the form of the basals. Basal pieces wider than long, sub-pentagonal in form, the mesial angle above being scarcely perceptible. Radial pieces of unequal size and form; the first one in the left posterior lateral ray about as long as wide, and sub-pentagonal in form (its right superior lateral angle being a little truncated), while it supports above, a shorter quadrangular piece, which bears on its upper edge a still shorter, but wide pentagonal axillary piece, upon which the arms rest; anterior, and right anterior lateral rays, having the same number, form and proportions of pieces; left anterior lateral ray composed of four primary pieces, the first of which is pentagonal, and about as long as wide, the second as wide as the first, but much shorter, and quadrangular in form, the third quadrangular and nearly as long as wide, and the fourth very short, pentagonal, and bearing two arms on its upper sloping sides; right posterior ray composed of five primary, or body pieces, the first one of which is wider than long, and pentagonal in form, the second much shorter than wide, and sub-pentagonal, the third about the size of the first, but quadrangular, the fourth very short, and the fifth wider than long, pentagonal in form, and, like the last piece in each of the other two rays, bearing above, two arms. First anal piece, as usual, resting between the lateral superior sloping sides of the first piece of the left posterior ray, and the second of the right, and connecting on each side with the succeeding pieces of these rays above, while it appears to support one or two other smaller pieces in direct succession above.