of barren rocks, with lichens their only vegetation, the summit of Roan, and many other peaks, is a smooth, grassy slope, of the most vivid green, dotted with clumps of Alnus viridis, and Rhododendron catawbiense, the soil one or two feet in depth, rich and black. How this amount of humus was accumulated on these summits, and what cause destroyed the forests which its existence would seem to indicate as formerly existing, are questions not easily answered.

The valleys are very fertile, and adapted to almost any crop. At an elevation of 3,000 to 4,000 feet occurs a belt of the most magnificent forest trees I have ever seen-hundreds of chestnuts, sugar maples, lindens, tulip trees, yellow birches, buck-eyes-some from 4 to 7 feet in diameter, and rising 70 to 80 feet without a limb. One chestnut measured 24 feet in circumference, and one black cherry measured 19 feet. Thorn bushes are as large as old apple trees with dwarf buck-eyes and yellow birches, looked like old orchards of vast extent.

IV. Flora.

Ascending the mountain, the vegetation takes on a northern aspect, Hemlocks abound till near the summit, where they are replaced by Abies Fraseri, the characteristic species of these summits.

Anemone nemorosa, Oxalis acetosella, Rubus odoratus, Ribes lacustre and prostratum, Aster acuminatus, Habenaria articulata, Veratrum viride, Lycopodium lucidulum, and similar species, remind one of the woods of Maine or New Hampshire.

The peculiar flora of the upper 1,000 feet, greatly resembles in habit that of the White Mountains, but very few species are the same. Paronychia argyrocoma, Lycopodium selago and Alnus viridis, are almost the only plants that occur to me as identical in the two localities, and these in the White Mountains are found in Crawford Notch, while in Roan they are near the summit. Arenaria grænlandica is replaced by A. glabra, Solidago thyrsoidea by S. glomerata; Geum radiatum of the North is a variety of that found here; the two dwarf Nabali of White Mountains are represented by a new species, N. roanensis, Rhododendron lapponicum (four inches high) by magnificent R. catawbiense, covering the summit with its domes of inflorescence six to eight feet in diameter, Castilleia pallida by C. coccinea.

So that, in general, the species peculiar to these mountains are hardly sub-alpine, and thus continuous with similar species further

north, but are rather apparent instances of local variation, many species being confined to very limited localities.

On Mount Washington, a few rods will often give the same plant in bud, flower, and fruit, as a north or south exposure, a precipice, or a snow-drift may retard or accelerate growth; but on these southern mountains no such difference obtains any more than in the valleys below.

On this communication Mr. J. W. POWELL remarked that the uniformity in the altitudes of the peaks is a feature resulting from the fact that the general mass out of which they have been carved by erosion possesses a plateau structure. The elevation of that region was distributed in its effects with an approach to uniformity over a wide extent of country, and was unaccompanied by those sharp flexings or the protrusions of abrupt mountain cores, which are encountered in some portions of the Appalachians and other mountainous regions. The individual masses and ranges in the Cumberland region are the work of erosion-the general process of land sculpture acting upon a broad platform, excavating broad valleys and narrow gorges, and leaving the peaks and ridges as cameosmere remnants left in the general degradation of the whole region. Prof. Powell exemplified the process by citing the Uinta Mountains as a broad platform similarly carved by an extensive erosion. The following paper was read by LESTER F. WARD, entitled

FIELD AND CLOSET NOTES ON THE FLORA OF WASHINGTON AND VICINITY.

[Abstract.*]

Introductory Remarks.

This paper has resulted from a suggestion made to the writer in the spring of 1880, by a member of the Committee on Publications of this Society, relative to the need that exists for some special

*Mr. Ward's communication presented to the Society only a brief notice of the principal points of a monograph which he had prepared upon the flora of the District of Columbia. In view of the local character of his subject, and of the thorough and commendable manner in which it had been elaborated, the Committee on Communications recommended, and the General Committee authorized, the printing of a very full and copious abstract of the paper, which is given herewith.

treatise on the flora of this vicinity, and for a new and revised catalogue of the plants. While there now exists a provisional catalogue containing most of the species which have been collected or observed by botanists during the past six or seven years, it consists of so many small annual accretions, due to constant new discoveries, and contains withal so many blemishes and imperfections, incident to its hasty compilation and irregular growth, that it has ceased, in great part, to meet the demands of the present time. The elaboration of a systematic catalogue of the local flora was not, however, at the outset at all contemplated, but merely the presentation of certain notes and special observations on particular species, which had been made in the course of some nine years of pretty close attention to the vegetation, and somewhat varied and exhaustive field studies in this locality.

The flowering-time of most species here is much earlier than that given in the manuals, and is, moreover, in many cases, very peculiar and anomalous, rendering it important to collectors as well as interesting to botanists to have it definitely stated for a large proportion of the plants. It being thus necessary to extend the enumeration so far, it was thought that the remainder might as well be added, thus rendering it a complete catalogue of all the vascular plants known to occur here at the present time. To these has been appended the list of musci and hepatica prepared by the late Mr. Rudolph Oldberg for the Flora Columbiana, which has been left unchanged except in so far as was required to make it conform strictly to Sullivant's work which has long been the standard for this country. Dr. E. Foreman has also furnished the names of a few of the Characea collected by himself, and named by Prof. Farlow, of Cambridge, which, in the present unsettled state of the classification of the cryptogams, have, for convenience, been placed at the foot of the series.

In undertaking this compilation I have endeavored to resist the usual temptation of catalogue makers to expand their lists beyond the proportions which are strictly warranted by the concrete facts as revealed by specimens actually collected or species authentically observed; but have been content to set down only such as I can either personally vouch for, or as are vouched for by others who have something more substantial than memory to rely upon; preferring that a few species actually occuring but not yet seen should be omitted and afterwards supplied, rather than that others, sup

posed to exist, but which cannot be found, should stand in the catalogue to be apologized for to those who would be glad to obtain them. A few species, however, which are positively known to have once occured within our limits, but which have been obliterated within the recollection of persons now living, have been retained, as well as several of which only a single specimen has been found; but in all such cases the facts are fully stated in the notes accompanying each plant.

Range of the Local Flora.

The extent of territory which has of late years been tacitly recognized by botanists here as constituting the area of what has been called the Flora Columbiana is limited on the north by the Great Falls of the Potomac, and on the south by the Mount Vernon estate in Virginia, and Marshall's just opposite this on the Maryland side of the river, while it may reach back from the river as far as the divide to the east, and as far westward as the foot of the Blue Ridge, so as not to embrace any of the peculiarly mountain forms. Practically, however, the east and west range is much more restricted and only extends a few miles in either direction.

Comparison of the Flora of 1830 with that of 1880.

Washington and its vicinity has long been a field of botanical research. The year 1825 witnessed the dissolution of the Washington Botanical Society, which had for many years cultivated the science, and the same year also saw the formation of the Botanic Club, which continued the work, and in one respect, at least, excelled the former in usefulness, since it has handed down to us of the present generation a valuable record in the form of a catalogue of the plants then known to exist in this locality. This catalogue, which was fittingly entitled Flora Columbiance Prodromus, and claimed to exhibit "a list of all the plants which have as yet been collected," though now rare, and long out of print, is still to be found in a few botanical libraries.

I have succeeded in securing a copy of this work, and have been deeply interested in comparing the results then reached with those which we are now able to present. A few of these comparisons are well worth reproducing.

It should be premised that the Prodromus is arranged on the

artificial system of Linnaeus, so that before the plants could be placed in juxtaposition they required to be re-arranged. This, however, was not the principal difficulty. Such extensive changes have taken place in the names of plants during the fifty years which have elapsed since that work appeared, (1830,) that it is only with the greatest difficulty that they can be identified. After much labor, I have succeeded in identifying the greater part of them, and in thus ascertaining about to what extent the two lists are in unison. This also reveals the extent to which each overlaps the other, and thus affords a sort of rude index to the changes which our flora has undergone in half a century. There are, however, as will be seen, many qualifying considerations which greatly influence these conclusions and diminish the value of the data compared.

The whole number of distinct names (species and varieties) enumerated in the Prodromus is 919. Of these 59 are mere synonyms or duplicate names for the same plant, leaving 860 distinct plants. I have succeeded in identifying 708 of these with certainty as among those now found, and six others, not yet clearly identified, should probably be placed in this class. This leaves 146 enumerated in the old catalogue which have not been found in recent investigations. [A classified list of these plants was presented and commented upon somewhat in detail.]

With regard to these 146 species, it must not be hastily concluded that they represent the disappearance from our flora of that number of plants. While they doubtless indicate such a movement to a certain extent, there are ample evidences that many of them can be accounted for in other ways. After careful consideration, I have been able to divide them into four principal classes arising

out of

1st. Errors on the part of those early botanists in assigning to them the wrong names.

2d. The introduction into the catalogue of adventitious and even of mere cultivated species, never belonging to the flora of the place. 3d. The undue extension by those collectors of the range of the local flora so as to make it embrace a portion of the maritime vegetation of the Lower Potomac or the Chesapeake Bay, and also the mountain flora of the Blue Ridge.

4th. The actual extermination and disappearance of indigenous plants during the fifty years that have intervened since they made their researches.