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with B. obliquum, but not in the barren frond, which, although bipinnate, has not narrower divisions. They are simply more coarsely crenate and more coriaceous. This may of course be not at all B. obliquum of Dr. Lawson, and I had regarded it as a variety of the B. lunarioides. I can add nothing further, as I have not seen many specimens of this fern. I have a variety of it collected at Lake Memphramagog, C E., in 1862, by Mrs. J. H. Thompson, which would be in the same relation to B. lunarioides that the variety y. simplex is to B. Virginicum. The sterile branch is almost twice pinnate, with few wedge-shaped minutely-toothed lobes; the fertile branch is also almost or entirely twice pinnate but the whole specimen has this peculiarity, that instead of there being three barren branchlets, and one fertile, there are three fertile and one barren.

BOTRYCHIUM LUNARIA.-North side of Island of Orleans, J. F. Whiteaves, F.G.S.; and Rivière du Loup en bas.

OPHIOGLOSSUM VULGATUM.-Melbourne, C. E., where exceedingly fine specimens are to be found, Miss Isabella McIntosh, Burnside House, Montreal. This fern, with the Botrychium Lunaria mentioned above, are now for the first time recorded as being natives of Canada proper.

The above brief statement of the Lower Canadian ferns, intended as a supplement to Dr. Lawson's valuable paper, includes thirtyseven species, to which, if we add the six additional ones which are as yet peculiar to Upper Canada, we have a total of fortythree species of Canadian ferns. I enumerate the six above alluded to.

PELLEA ATROPURPUREA, Link.

CRYPTOGRAMMA ACROSTICHOIDES, R. Brown.

ASPLENIUM EBENEUM, Aiton.

WOODWARDIA VIRGINICA, Willdenow.

SCOLOPENDRIUM VULGARE, Smith.

POLYSTICHUM LONCHITIS, Roth.

There are, then, in Canada almost as many species of ferns as in Great Britain, and much is yet left for observation, particularly in Lower Canada,-where other species may, perhaps, be discovered; and we have also the investigation of varieties to interest us.

There are forty-nine species mentioned by Gray as being in the northern United States; and of these a good number, as Lygodium palmatum, Swartz, Schizaea pusilla, Pursh, and others, are not

to be looked for in Canada, from its northern position. On the other hand, Dr. Lawson's lists include Asplenium viride, Hudson, Botrychium lunaria, Swartz, and others which are beyond Gray's stated limits, (see page 263). Should we, then, not find some Canadian ferns recorded by Gray or other American authorities, we must look to other countries of the same latitude, elevation, &c., as ours. Taking a general view, more than half of the Lower Canadian ferns are inhabitants of tracts of country not dry; they are found in open meadows, or swamps; the remainder grow upon rocks, with little moisture, as Woodsia Ilvensis, Cystopteris fragilis, (occasionally,) Allosorus gracilis, &c.; or upon rocky positions but requiring moisture, in which case they suffer during dry seasons, as Asplenium Trichomanes, &c. Not a few grow in either dry or damp positions, in shade or sunshine, when different varieties may be looked for; while a change of habit, such as is produced by clearing land, proves fatal to some species. A northern aspect is also sometimes noticed. What the progress of civilization may do in affecting the ferns, time will evince, as I have noticed ferns slowly disappearing; though the loss of species will of course require long lapses of time. For instance, have we any record what were the ferns of Europe, or of Great Britain, some centuries ago ?

With regard to Quebec, one of the localities indicated in the above notes, the Honorable William Sheppard, who kindly furnished me with a list of the ferns to be found there, is disposed to think that some more species than he has named might be discovered. He was guided by notes, and by memory, as his own collection was unfortunately destroyed by fire some years ago.

ON THE FOSSILS OF THE GENUS RUSOPHYCUS. By J. W. DAWSON, LL.D., F.R.S., &c.

The genus Rusophycus was established by Prof. Hall for certain transversely wrinkled impressions found in the Clinton group of Oneida County, New York, and supposed to be fossil sea-weeds. Objects of similar appearance have been detected by Mr. Billings in the Chazy sandstone of Grenville, and described by him under the name of R. Grenvillensis. They much resemble one of Prof. Hall's species, R. bilobatus, which is the type of short bilobate forms included in the genus. Similar markings, but of much smaller size, occur in the Lower Carboniferous of Nova Scotia, and have been described and figured by the writer as probably casts of the lower extremities of worm-burrows, in the Journal of the Geological Society of London, vol. xiv, p. 74. In the 12th volume of the same journal, Mr. Salter had described small bilobate impressions, not striated transversely, from the Longmynd rocks of England, under the name Arenicolites didyma. He supposed them to be burrows of worms.

[graphic]

Fig. 1. Rusophycus Grenvillensis, var. a, half nat. size.

I had an opportunity last summer, in company with Mr. J. A. Bothwell, B.A., to examine the locality of the Grenville specimens, and found them to be quite abundant in certain layers of sandstone alternating with shale on the bank of the Grenville canal. The facts obtained from their study in place enable me to throw some light on their probable nature, and possibly to rescue them

from the convenient group of fucoids, into which paleontologists have thrown so many obscure and doubtful fossils.

Mr. Billings describes the species as follows:

"This species is found in the form of irregular, oblong-ovate or depressed hemispherical masses, one end usually divided into two

[graphic][merged small][merged small]

parts by a furrow of more or less depth. The whole mass is generally crossed by numerous undulating wrinkles, which have a transverse direction to that of the furrow. The more common dimensions are from three to four inches in length, and from

Fig. 3. Rusophycus carbonarius.

two and a half to three and a half in breadth, but occasionally specimens occur much larger and also smaller; one of them is nine and a half inches by five and a half, and, in addition to the principal groove, exhibits two or three obscure furrows on each side."

To this description it is only necessary to add, that, in comparing a large number of specimens, many diversities are apparent in the relief of the forms, in the extent of the longitudinal furrow, and in the number of the transverse wrinkles. The two lobes are also most frequently slightly unequal in their relief; and some of the specimens slope gradually at one end, and are thus somewhat elongated. In all cases, however, the general form is the same, the longitudinal and transverse furrows are constant, and the former is always more strongly marked at one extremity of the fossil. The specimens have no indication of a stem or stalk; though a cast of a worm-burrow or shrinkage-crack sometimes simulates such an organ.

In viewing these fossils and the surfaces of the beds containing them, it appeared evident that they are in reality casts of hollows or holes excavated in clay, and filled with sand which has taken and retained in its consolidated state the impression of their forms. The supposed fossils project from the lower surface of the sandstone, where this rests on friable, dark grey shale. They have the same appearance with the surfaces of the beds of sandstone, and show no traces of organic matter. There are on the same surfaces casts of worm-tracks, also in relief, and which sometimes extend over the specimens of Rusophycus. There are also on these surfaces rows of wrinkles, or casts of furrows similar to those of Rusophycus ; and some of these form trails to or from the ends of the latter. (Fig. 2, a.) Casts of shrinkage-cracks in relief, also occur on the same surfaces. Large specimens of Rusophycus sometimes overlap small ones in such a manner as to show that they must have been scooped out of the clay. On the other hand, if the supposed fucoids were really of that character, they must have been solid masses or vesicles, and in the former case must have left some trace of organic matter, while in the latter they could scarcely have impressed themselves so deeply on the clay.

These appearances can, I think, be explained on the supposition that some animal crawling on the soft mud at the bottom of shallow water, by means of feet which made a double series of transverse marks, was in the habit of excavating deep burrows for shelter or repose, and that these burrows were filled with drifted sand constituting the lower part of what is now a thin bed of darkcolored sandstone. The burrowing of the modern Limulus, as described by the writer in vol. vii of this journal, would produce a similar effect. I have not seen the burrows of Limulus in clay;

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