gave the specific name of Serpentinus, and described the points in which it differed from E. platyurus (Cope), a description of which had been given at a meeting of the Society nine years ago, and was published in its Transactions.

Professor Cope also communicated evidence of the existence of a new species of Mastodon in the United States, and proposed for it the specific name M. tremontinus.

Mr. Chase called attention to some experimental results, illustrating his 6th, 7th and 10th fundamental propositions of central force.

Professor Blazius read a paper entitled "The progress in Meteorology, and its tendency during the last twenty-five years; with some supplementary notes to a recent English work bearing that title.

Pending nominations 830, 831, 832, 833 and 834 were read.

And the meeting was adjourned.

Stated Meeting, March 16th, 1877.

Present, 12 members.

Vice-President, Mr. PRICE, in the Chair.

Mr. McKean a newly elected member was introduced to the presiding officer and took his seat.

Letters accepting membership were received from Prof. J. M. Hart, dated 228 S. Broad Street, Philadelphia, March 21, 1877; and from Prof. F. Reuleaux, dated Berlin, Feb. 20, 1877.

Letters of acknowledgment were received from E. A. Barber, dated West Chester, Pa., March 12, 1877, (73, 75, 80); the Lenox Library, dated New York, March 14, 1877, (96, 98); and Prof. J. J. Stevenson, dated 314 W. Thirtieth Street, New York, March 7, 1877 (65 to 98).

A letter of envoy was received from Prof. Daniel Kirk

wood, dated Bloomington, Indiana, March 8th, 1877, with a MSS. communication.

Donations for the Library were received from the Royal Society, New South Wales; the Editors of the Flora Batava; the Royal Belgian Academy; the Revue Politique; the M. C. L., Cambridge, Mass.; Silliman's Journal; New Jersey Historical Society; Astor Library; Mr. E. A. Barber, Prof. P. Frazer, Jr., Dr. Hewson Bache; the Medical News; Journal of Pharmacy; Franklin Institute and Penn Monthly ; War Department at Washington, and Don J. Ramon de Ybarrola, of Mexico.

A communication was read by the Secretary entitled, "On Eight Meteoric Fireballs, &c., by Daniel Kirkwood, Professor of Mathematics, Indiana University, Bloomington, Indiana."

Prof. Blazius continued the reading of his paper on "The tendency of modern meteorology."

Dr. Wood communicated a paper entitled "On the asserted antagonism of Nicotia and Strychnia, by Francis L. Haynes."

The Secretary communicated a paper entitled, "Notes on the results of a survey of the iron ore beds of the Juniata District of the Second Geological Survey of Pennsylvania by John H. Dewees."

Prof. Cope exhibited and described a cast of the brain. cavity of Coryphodon elephantopus, of which a complete skeleton exists, and discussed the homologies of the organ, and showed that the genus to which the animal belongs properly constitutes a fourth sub-order of mammalia lower in type than the Marsupialia.

Pending nominations Nos. 830, 831, 832, 833, and 834 were read.

Prof. Chase offered the following preamble and resolutions, which were seconded, discussed and adopted:

Whereas, It is of the greatest importance that the investigation of natural phenomena, such as the origin and migrations of creatures, noxious

to agriculture, should be directed by disciplined men of science, of acknowledged ability and trustworthiness, and

Whereas, This Society has been informed that a vacancy may occur in the post of Commissioner of Agriculture in the Department of the Interior, and

Whereas, The name of our fellow member, and distinguished naturalist and entomologist, Dr. John L. LeConte, has been put forward for recommendation to the President for said appointment, therefore

Resolved, That this Society heartily endorse such recommendation.

Prof. Frazer offered the following resolution :

Resolved, That this Society recommend to its members in the presentation of papers containing references to length, weight and capacity, to add to such units as they may deem preferable, the metric units.

Dr. Rogers offered the following amendment:

And also, That those who may use the metrical system shall convert the same into the English.

The resolution and amendment were ordered to be published on the card of notice for the next meeting, and discussion on their merits was postponed.

The meeting was theu adjourned.

(Continued on page 661.)

On the Progress of the North American Carboniferous Flora, in prepara tion for the Second Geological Survey of Pennsylvania.

BY L. LESQUEREUX.

(Read before the American Philosophical Society, January 5, 1877.)

The purpose of this memoir is to give a short account of the progress which has been made, to this day, in the preparation of the North American Coal Flora as one volume of the current Reports of the Second Geological Survey of Pennsylvania.

At first it seemed appropriate to prepare for publication, and in order to preserve the right of priority of names, a catalogue of the species which have to be described in the Flora, and to define the essential points of the classification, especially the generic divisions.

Details of classification, however, cannot be positively fixed before all the materials used in the preparation of the descriptions of the species have been definitely examined. Then the manuscript of the flora will be ready for the printer and a synopsis of it would be useless. Moreover, a mere enumeration of names would offer little of general interest.

It is therefore more advisable to give in advance an exposé of the plan which has been followed in the researches deemed necessary for the preparation of the work; of the available sources of information; of the materials, when and where collected for it; of the point arrived at until now, and, therefore, of the more interesting data which have to be exposed in the publication of this Flora.

Those who have ever examined what is generally called specimens of coal plants, know that they generally represent parts of trunks, whose surface is marked by peculiar impressions; or branches without leaves, whose relation is recognized also by the scars upon their bark; or, for the ferns, especially, fragments or pinnæ of fronds with leaflets, or more generally, of detached pinnules, which, though they may be beautiful, do not give, when considered separately, an idea of the general or true character of the vegetable to which they belong. The classification of the living species of the great family of the ferns is derived more especially from the characters of their fructifications. In the coal, though the ferns constitute by far the greatest part of the vegetation, their fructifications are rarely found, and when found, they are mostly attached to branches or pinnæ separated from the sterile fronds, which then, were, as they are now, of.en very different in aspect and characters from the fruiting ones. Hence it is very difficult to ascertain their correlation ; and thus the paleobotanist may place in one genus a sterile branch when he has to describe the fertile pinna of the same tern, in another. Long ribbon leaves, hard fruits of various shape, also are frequently seen in the shale of the coal; but these are most rarely, if ever found attached PROC. AMER. PHILOS. SOC. XVI. 99. 2x

to stems, and, therefore the relation of many of them to the plants which they represent prevents their reference to original types, and forces, for their description, an artificial classification which the discovery of a single specimen may overthrow. Hence it happens that, in the pursuit of his researches to recognize the specific characters or even the more distant relations of the vegetable fragments, the paleontologist is forced to look for and to compare a large number of specimens before he is able to fix their references. The subdivisions of the leaves or fronds of ferns, the pinnæ and pinnules, have not between the same species that kind of likeness or affinity of shape remarked between the leaves of dicotyledonous plants. The modifications of form are not only extremely numerous, but present such an anomalous diversity, that botanists unacquainted with this section of natural history could often suppose no generic relation between some of the leaflets which represent the same species. One of the most common ferns of the middle coal measures, a Neuropteris, for instance, is nearly always found in detached, fine, large, cordate-lanceolate leaflets, which sometimes measure four to five inches in length and two or three inches in diameter. Some small round or broadly oval pinnules are generally found mixed with those large leaves; they are not even half an inch in diameter; and though they have a similar character of nervation, the difference in shape and size is so marked that they were of course described under a different specific name. Lindley and Hutton were the first to suppose, from their coincidence of local distribution, that they might possibly represent parts of the same plant. Since then, and long afterwards, large branches of fronds have been discovered in this country with the two forms of leaves attached to the same pedicel, the large leaves being borne upon a short stalk, with two small leaflets attached to their base. A number of cases of the same kind might be mentioned; but this one is sufficient, and I quote it not merely to show how great are the difficulties encountered by the botanist in the study of coal plants and what persistence it demands, but to prove that the discoveries made in the coal flora of this continent render now to European paleontologists the same amount of assistance that we have received from their works in former times.

The remains of coal plants, generally pleasant to the eye by their graceful shape, and some of them of very peculiar forms, widely apart from those which are generally observable in the vegetation of our time, could not but, as wonderful productions of nature, excite the interest of the first investigators of the carboniferous measures of Pennsylvania. Already in 1818, Steinhauer had published in the Transactions of the American Philosophical Society his Fossil reliquia, where remains of plants now referable to Calamites, Lepidodendron, Ulodendron, Artisia, Sigillaria, and Stigmaria, are figured and described under the collective name of Phytolithes. He does not represent any kind of fern; but he mentions in the introduction that most of the specimens of fossil plants from the carboniferous are Filices (ferns). After him, in 1820, Granger mentions without descrip tions a few specimens of coal plants from Zanesville, Ohio. From that time