ART. XV.-Lower Carboniferous Limestone in Ohio; by Prof. E. B. ANDREWS.

FOR several years I have suspected that a certain limestone in southeastern Ohio should be classed with those of the Lower Carboniferous limestones. The supposition was entirely contrary to the "traditions of the elders," and furthermore, the limestone was above the principal range of conglomerate which has been ever regarded as true Coal-measure conglomerate. In the prosecution of the Ohio Geological Survey, in the 2d district, entrusted to me, I find that the conglomerate referred to is a Waverly conglomerate; that it is separated from the base of the productive Coal-measures by an upper Waverly sandstone group, rich in fossils, which I have called the Logan sandstone group, and that resting upon this group is, in many places, a limestone, called the Maxville limestone, which is a true Lower Carboniferous limestone. This limestone is not a continuous deposit but has only a local development here and there, always resting, however, upon the fine-grained Logan sandstone group. It was deposited in quiet basins along a uniform horizon. Generally, there is an iron ore adhering to the top of the limestone. There is no evidence that the local deposits were once continuous and united and were subsequently separated by erosion. The stratigraphical position of the limestone and the contained fossils led me to suspect that we had in it an Ohio representative of the Chester limestone of the Illinois Reports. This opinion has been confirmed. Prof. F. B. Meek, now engaged in the study of our Ohio fossils, has sent me the following report in regard to the fossils of the Maxville limestone:—

"List of species and genera.

1. Zaphrentis. A small undetermined curved conical species.

2. Scaphiocrinus decadactylus Hall? Described from the Chester group.

3. Productus pileiformis McChesney. Described from the Chester group. Thought by Mr. Davidson to be the same as P. cora d'Orbigny.

4. Productus elegans N. and P. Described from the Chester group. Some of the specimens may be the form Prof. McChesney described from the same horizon under the name P. fasciculatus.

5. Chonetes. Undetermined species.

6. Athyris subquadrata Hall. Described from the Chester (Kaskaskia) group. 7. Athyris trinuclea Hall. sp. Described from the St Louis (Warsaw) group.

8. Spirifer (Martinia) contractus M. and W. Described from the Chester group. 9. Spirifer. Undetermined fragments of perhaps two species.

10. Terebratula. An undetermined, small oval species showing the fine punctures under a lens.

11. Aviculopecten. Undetermined species.

12. Allorisma. Undetermined fragments, apparently like A. antiqua Swallow, described from the Chester group.

13. Naticopsis. A small undetermined species.

14. Straparollus perspectivus Swallow, sp. Probably a more elevated form of S. planidorsatus M. and W. Both were described from the Chester group.

15. Bellerophon sublaevis Hall. Described from the St. Louis (Warsaw) limestone. 16. Pleurotomaria. A small undetermined cast.

17. Nautilus. A small undetermined compressed, discoidal species with the very narrow periphery truncated.

18. Nautilus. A large sub-discoid undetermined species, with an open umbilicus and only slightly embracing volutions that are somewhat wider transversely than dorso-ventrally, and provided with a row of obscure nodes around near the middle of each side. Very nearly allied to N. spectabilis M. and W. from the Chester group, but more compressed and having narrower and apparently one or two more volutions. Specimens mere fragments." In his letter Prof. Meek adds: "From these fossils, it is clearly evident that the limestone, from which they were obtained, belongs, as you had supposed, to the horizon of the Lower Carboniferous limestone series of the Western States. They also show that it does not belong to any of the inferior members of that series.

Of the 18 or 20 species of fossils sent from this rock, about one half are represented in the collection only by specimens that are too imperfect for specific identification; though none of them, so far as their characters can be made out, appear to be allied to known forms from any horizon below the St. Louis limestone.

Of the remaining species, five can be identified confidently with Chester forms, and three others are either identical with Chester species, or most closely allied to forms of that age. Hence we may safely say that eight of the species are Chester types. Two, however, seem to be identical with species described from the St. Louis limestone farther west.

From these facts I can scarcely doubt that we have in these local masses of limestone a representation of the Chester group of the Lower Carboniferous limestone series; though it is possible that there may also be some representation of the St. Louis limestone of the same series at some of the outcrops.

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The discovery of these beds is, I believe, the first indication we have had of the existence of any member of the Lower Carboniferous limestone series of the West in Ohio. They also seem to show that the old Carboniferous sea did not extend to this region during the deposition of any but the later members of the lower limestone series, although we know it had done so previously, that is, during the older Waverly period."

The largest and best development of the Maxville limestone is in Muskingum county, in the vicinity of Newtonville, where it is from 15 to 20 feet thick. Although here within the geographical limits of the productive coal-measures, it is well exposed in the deep valleys of Jonathan's creek and other tributaries of the Moxahala creek. It is also found in Perry, Hocking, Vinton, Jackson and Scioto counties.

A single analysis of the stone showed it to be a double carbonate of lime and magnesia.

ART. XVI.-Brief Contributions to Zoology from the Museum of Yale College. No. XI. Descriptions of some imperfectly known and new Ascidians from New England; by A. E. VERRILL. (Continued from page 56.)

Cynthia stellifera Verrill, sp. nov. Figures 5, 6.

Body depressed, oval or elliptical, attached by a broad, expanded base, with thin edges. Integument firm, thick, and opaque, the surface uneven with irregular, imperfectly reticulated wrinkles, between which the surface is somewhat raised, producing an irregularly tessellated appearance, most conspicuous above; the raised parts are minutely granulous. A somewhat elevated, rounded ridge passes from the lowest end over the top and between the tubes, connecting them together. The tubes are quadrangular, low, truncate, nearly equal, a little divergent, situated toward the larger end, a little to one side, and separated by a space greater than their diameters; both have similar apertures, cross-shaped in partial expansion, and surrounded by four larger papillose lobes, between which there are many smaller ones (fig. 6, b).

5.

Color of the body, when living, reddish brown, ferruginous, or purplish brown, often yellowish toward the margin, the median ridge yellowish brown; aper

tures sometimes bright orange within,

in the area immediately around the openings purplish, with minute, radiating streaks of flake-white; the four

b

6.*

a

large lobes are brownish, with numerous small specks and streaks of flake-white, which often predominate over the groundcolor.

The largest specimens are about an inch in length, and half an inch in breadth.

At New Haven Light and Savin Rock, near the entrance of New Haven Harbor, adhering to the under side of stones at lowwater mark,-A. E. Verrill.

Cynthia monoceros.

Ascidia monoceros Möller, Index Mollusc. Groenlandiæ in Kroyer's Naturhist. Tidsskrift, iv, p. 95, 1842.

Cynthia condylomata Packard, Invert. of Lab., in Mem. Boston Soc. Nat. Hist., i, p. 277, 1867; Binney, op. cit., p. 19, Pl. xxiii, fig. 324, 1870.

An examination of Dr. Packard's original specimens shows that they are identical with Möller's species. It differs widely

* Figure 6.-Cynthia stellifera V.; a, view from above, natural size; b, view of one of the tubes from above, enlarged about three diameters.

AM. JOUR. SCI.-THIRD SERIES, VOL. I, No. 2.- FEB., 1871.

from all others from the American coast in the elevated tubercles of the surface and the prominent, conical summit, between the tubes.

According to Möller the color is pale red, with red orifices. It is an Arctic species, not yet observed south of Labrador, and the Banks of Newfoundland. From the latter locality I have seen many fine specimens, collected by T. M. Coffin and J. P. Haskell, some of them 3 inches high and 75 in diameter.

Cynthia carnea Verrill. Figures 7, 8, 9.

Ascidia carnea Agassiz, Proc. American Assoc. for Adv. Sci., ii, p. 159, 1850, (description insufficient); Binney in Gould's Invertebrata of Mass., 2nd ed., p. 25, Pl. xxiv, figures 334, 335, 1870, (young).

Cynthia gutta Stimpson, Proc. Boston Soc. Nat. Hist., iv, p. 231, 1852, (young); Binney, op. cit., p. 19, 1870.

Cynthia placenta (pars) Packard, Mem. Boston Soc. Nat. Hist., i. p. 277, 1867; Binney, op. cit., p. 19, Pl. xxiii, figure 322, 1870; Verrill, Amer. Journ. Sci., xlix, p. 424, 1870.

When adult, this species is often two or three inches high and about an inch broad at the base, which is broadly adherent and thin at the margin.

The body is elongated, subconical, cylindrical, or urn-shaped and swollen above the middle (fig. 7), according to the state of expansion, and very changeable in form. The integument is rough, thick, firm, opaque, and reticulated with deep wrinkles, which are very conspicuous in contraction, but less numerous at the base, the interstices are raised and thickly covered with small granules. The tubes are terminal, subequal, divergent, enlarged at the bases, moderately elongated, tapering to the tips, with small square apertures. The anal tube is generally the most bent, and a little the longest. In contraction the body is low, conical, or hemispherical, with the surface coarse and rough, conspicuously reticulated and granulated; the tubes form low, four-lobed verrucæ, covered with rough granulous papilla; the apertures are cross-shaped.

7.

The color, when living and expanded, is dark reddish brown, or orange-brown, darker below, the wrinkles lighter than the interstices and often salmon-colored; the upper parts, especially the summit between the apertures, are deep salmon. The apertures are orange-red or salmon-color within, and surrounded by a ring of bright red. The ovaries were filled with deep red eggs and embryos, and discharged the active tadpole-shaped larvæ early in September.

When younger the form is quite different (fig. 8), and when contracted corresponds in part with

Packard's C. placenta.* In expansion, however, the central

* By an examination of Dr. Packard's specimens I find that one of them belongs to a quite distinct species, having the surface minutely papillose and covered with closely adhering grains of sand.

portion of the body rises up and becomes prominent, subconical, rounded at the summit, and terminated by two prominent, nearly equal tubes, which are large at the base and taper rapidly to the square apertures. The base is broadly expanded, with a thin extended margin, and adheres very closely, so that it is often impossible to detach it without rupturing the integument. The ovaries are filled with bright red eggs and embryos, nearly the color of blood. The surface is wrinkled and reticulated nearly as in the adult, except that it is not so rough; the margin of the base is nearly smooth.

8.

The color is similar to that of the adult, though usually lighter; the wrinkles are generally salmon-color and the raised interstices dull reddish brown; the upper part between the tubes lighter, often salmon-color; the apertures bright red or orange inside.

When quite young (fig. 9) the body is very low and adheres by a broad base, which is very thin at the edge and expands in the form of a whitish margin around the slightly raised central part, which is oval or elliptical, and rounded above, in expansion, with the two small apertures on slightly raised tubes, one a little larger than the other. In contraction the body is nearly flat, the apertures sessile. In this state the integument is smooth at and near the margin, and only slightly roughened or indistinctly reticulated in the central parts. At a little earlier stage of growth it is entirely smooth.

The color is bright light red, deep pink-color, or blood-red, the raised interstices, when apparent, are deeper red; a bright pink or red line usually connects the two apertures, which are bright red; the thin margin of the base is whitish or light flesh-color, and transparent. The ovaries are filled, as in the older ones, with blood-red eggs and embryos. In this stage of growth it corresponds perfectly with A. carnea Agassiz, as figured by Binney, and probably with A. gutta Stimpson, though the latter may possibly be the similar young of some other species.

9.

Eastport Harbor, at extreme low-water of spring tides, under stones, rare; in 10 to 50 fathoms, on dead shells, stones, large ascidians, and Modiola modiolus, more common, but not abundant,-Expeditions of 1863, '64, '68, '70; South Bay, Lubec, 10 to 15 fathoms, shelly, not rare,-Exp. 1868, '70; off East Quoddy Light, young on smooth stones in 80 fathoms, abundant,Exp. 1868; Off Head Harbor, Campo Bello L., in 100 to 120 fathoms, shelly,-Exp. 1870; Grand Menan, 15 to 20 fathoms,