carrying out his experiments on tubercle bacilli.

THE American Forestry Association proposed holding its annual peripatetic meeting in southern New Jersey from May 16th to May 19th. The privileges of this expedition are open to all members of the American Forestry Association, New Jersey Forestry Association and Pennsylvania Forestry Association. On May 15th Prof. B. E. Fernow was to deliver an illustrated lecture at Camden, from which place the party would start, going down the Delaware by steamboat, visiting all places of interest along the shore from Cape May to Atlantic City and in the pines. On the evening of May 17th an illustrated lecture was to be delivered in Atlantic City by Prof. Joseph Rothrock, Forestry Commissioner for Pennsylvania.

Ar a meeting of the Fellows of the Royal Botanical Society held in the Societies' gardens at Regent's Park, London, the question of the desirability of opening the gardens to the public on Bank holidays was discussed. It was stated at the same meeting that unless some fresh source of income could be obtained the gardens could not be kept up.

Ar the spring meeting of the Iron and Steel Institute the Bessemer gold medal of 1895 was unanimously awarded to Henry Marion Howe, of Boston, in recognition of his contributions to metallurgical literature. Among the previous recipients of the medal were Peter Cooper, Abram S. Hewitt, Alexander L. Holley and John Fritz. Mr. Howe's most important work is a treatise on the 'Metallurgy of Steel,' which was published in 1890 and for which he received a prize of $500 from the Société d' Encouragement of Paris.

THE 66th anniversary meeting of the Zoological Society of London was held on April 29th. The chair was taken by Sir William H. Flower. The report of the

Council stated that the silver medal had been awarded to Mr. Henry H. Johnston, Commissioner for British Central Africa, for his distinguished services to all branches of natural history. The total receipts of the Society for 1894 amounted to £25,107, a decrease of £1,110 being attributed to the unfavorable weather of the past year. The expenditure amounted to £23,616, a decrease of £1,661. The number of animals in the Zoölogical Gardens on December 31st last was 2,563, of which 669 were mammals, About 30 1,427 birds and 467 reptiles. species of mammals, 12 of birds and one of reptiles had bred in the gardens during last summer. Sir William H. Flower was reelected president.-London Times.

Mr. Hubbard's subject was 'Russia.' He considered it in the light of his own observations while making an extensive journey through that country in 1881. Its climate, physiographic features, government and the customs and conditions of its people were all graphically portrayed. At the close of the address a series of views were shown upon the screen.

In response to a motion by Prof. Simon Newcomb, seconded by Postmaster General Wilson, the large audience gave Mr. Hubbard a hearty vote of thanks for his address. J. S. DILLER, Secretary.

BIOLOGICAL SOCIETY OF WASHINGTON.

AT the meeting on May 4th, Mr. Charles Torrey Simpson read a paper On the Geo

graphical Distribution of the Naiades,' an abstract of a paper on classification and distribution soon to be published.

After stating that the classification adopted by most authors, in which the family Unionida is founded on forms without siphons, and the Mutelide on those in which they are developed, cannot stand, since these characters vary in the same genus or species, the writer showed that von Ihering's new definition of the families, in which the former was based on the embryonic state being a glochidium and the latter by its larvæ being a lasidium agreed with the shells. In the Unionida these are schizodont, in the Mutelida they are irregularly taxodont. The new arrangement shows the former family to be world-wide; the latter as belonging essentially to the southern hemisphere.

The Naiads are distributed in Geographical Provinces whose boundaries may be mountain chains which act as watersheds between river systems, deserts or oceans, but these do not always divide regions, which sometimes have no tangible barriers. In the Old World and South America these provinces essentially agree with those established by Sclater and Wallace; in North America they do not.

The Palearctic Region includes all Asia south to the Thibetan Plateau, and all the western part of the continent, all Europe and northern Africa, and all of North America west of the Great Cordillera; an area of 16,000,000 square miles, with only a few, not over 50, simple forms. The Oriental Region includes all of Asia south of the Himalayas, north to the Amoor, west to the Indus, Japan and the Malay Archipelago to the Salomon Islands. The forms are numerous, often heavy, distorted, elegantly sculptured, and closely related to those of the United States.

The Australian Region includes Australia, Tasmania and New Zealand, with a

few simple unios related to those of South America. Africa south of the Desert is another great region, the Ethiopian, containing the African Mutelida and small unios allied to those of India. South America is all included in another province, the Neotropical, the Andes proving a barrier to the passage of all forms except unios, which have crossed to the western slope. All the central United States drainage from West Florida to the Rio Grande, including, for the most part, the Great Lakes and the Mackenzie System, constitutes a wonderfully rich region of naiad life, having the finest and most varied forms of the globe. The waters of North America draining into the Atlantic are peopled by simple forms, which may have descended from those of the Mississippi Valley. Mexico and Central America constitute another region of naiad life, having three distinct faunas, an ancient one derived from the United States, a more recent one from that region, and a few immigrants from South America.

Mr. Simpson attempts to trace the development and past history of the naiads, and their evidence regarding past changes of land and sea and the Glacial Epoch.

The paper was illustrated by a sketchmap in colors, showing the different regions.

The second paper of the evening, 'The Other Side of the Nomenclature Question,' was by Dr. Erwin F. Smith, who spoke, in reply to a previous paper by Mr. F. V. Coville, against the unfounded claims put forth in behalf of the Botanical Club Check List. This list has introduced many radical changes into our existing botanical nomenclature without sufficient reason. The revival of the long disused generic names of Rafinesque et al., and the retro-active application of the rule "Once a synonym always a synonym," whereby many generic names of long standing have been discarded, are specially objectionable, and will not bear the light of criticism. Only a few people

are urging the adoption of these ultra rules. The best systematic botanists of the world are opposed to them, and there is such a widespread and determined opposition to them in the botanical fraternity generally, both in this country and in Europe, that the movement is certain to amount only to a lamentable schism. It has been claimed that nine-tenths of our American botanists are in favor of these rules, but such statements are wide of the mark. Some of these rules are in conflict with the Paris Code, and others claim to be a strict interpretation of it; but de Candolle himself, the author of this code, considered such interpretations of it as 'abuses,' and urged that the Paris Code of 1867 be so amended as to prevent the swamping of our nomenclature by ultra theorists.

One fact lost sight of by the movers of this new American system, for it has no following in Europe, is that science is an international affair, that the bulk of the botanical work of the world is done outside of the United States, and that even if we were all agreed on this side of the water, which is far from true, it would still be necessary to gain consent of botanists elsewhere before giving to these rules any more weight than mere suggestions. It will be time enough for American botanists to put them into practice when they have received the sanction of an International Botanical Congress. Another very strong objection to making radical changes in our botanical nomenclature is the extent to which botanical names are used in agriculture, forestry, horticulture, floriculture, pharmacy and medicine. There is nothing comparable to it in zoology. Only intolerable confusion can result from calling a plant by one name in botany and by another in horticulture or pharmacy, and it is surprising that the force of this argument was not perceived long ago. Finally, the Botanical Club rules do not have the sanction of the A. A. A. S., as

might be inferred from some statements which have been made, and the organization of the Club is so loose as to be a fatal objection to regarding its doings or recommendations as in any sense binding on American botanists, when these are opposed by counter-recommendations proceeding from the most famous botanists in the world. F. A. LUCAS, Secretary.

BOSTON SOCIETY OF NATURAL HISTORY, MAY 15.

Notes on the Dissection of a Chimpanzee, with Especial Reference to the Brain: PROF. THOMAS DWIGHT.

The Conditions of Escape of Gases from the Interior of the Earth: PROF. N. S. SHALER. SAMUEL HENSHAW,

electrified masses of air moving past the place of observation. I did not remark then, but I now see, that the electricity in these moving masses of air must, in all probability, have been chiefly positive to cause the variations which I observed, as I shall explain to you a little later.

§ 2. Soon after that time a recording atmospheric electrometer which I devised, to show by a photographic curve the continuous variation of electric potential at a fixed point, was established at the Kew Meteorological Observatory, and has been kept in regular action from the commencement of the year 1861 till the present time. It showed incessant variations quite of the same character, though not often as large, as those which I had observed on the seabeach of Arran.

Through the kindness of the Astronomer Royal, I am able to place before you this evening the photographic curves for the year 1893, produced by a similar recording electrometer which has been in action for many years at the Royal Observatory, Observatory, Geeenwich. They show, as you see, not infrequently, during several hours of the day or night, negative potential and rapid transitions from large positive to large negative. Those were certainly times of broken weather, with at least showers of rain, or snow, or hail. But throughout a very large proportion of the whole time the curve quite answers to the description of what I observed on the Arran sea-beach thirty-six years ago, except that the variations which it shows are not often of so large amount in proportion to the mean or to the minimums.

§3. Thinking over the subject now, we see that the gradual variations, minute after minute through so wide a range as the 3 or 4 to 1, which I frequently observed, and not infrequently rising to twenty times the ordinary minimum, must have been due * 'Electrostatics and Magnetism.'

to positively electrified masses of air, within a few hundred feet of the place of observation, wafted along with the gentle winds of 5 or 10 or 15 feet per second which were blowing at the time. If any comparably large quantities of negatively electrified air had been similarly carried past, it is quite certain that the minimum observed potential, instead of being in every case positive, would have been frequently large negative. § 4. Two fundamental questions in respect to the atmospheric electricity of fair weather force themselves on our attention:— (1) What is the cause of the prevalent positive potential in the air near the earth, the earth's potential being called zero? (2) How comes the lower air to be electrified to different electric densities whether positive or negative in different parts? Observations and laboratory experiments made within the last six or eight years, and particularly two remarkable discoveries made by Lenard, which I am going to describe to you, have contributed largely to answering the second of these questions.

§ 5. In an article 'On the Electrification of Air by a Water-jet,' by Magnus Maclean and Makita Goto,* experiments were described showing air to be negatively electrified by a jet of water shot vertically down through it from a fine nozzle into a basin of water about 60 centimeters below it. It seemed natural to suppose that the observed electrification was produced by the rush of the fine drops through the air; but Lenard conclusively proved, by elaborate and searching experiments, that it was in reality due chiefly, if not wholly, to the violent commotions of the drops impinging on the water surface of the receiving basin, and he found that the negative electrification of the air was greater when they were allowed to fall on a hard slab of any material thoroughly wetted by water than when they fell on a yielding surface of water several *Philosophical Magazine, 1890, second half-year.