density (dense enough to float glass). Probably since the internal friction of liquids vanishes with the relative velocity of layers, and since the apparent motions are magnified, there are eventually no frictional torques left to absorb whatever angular momenta may be renewed. The occurrence of direct and retrograde motions at the same time, separated sharply by a plane of demarcation suggests vortices. Above this plane particles move with about the same speed in one direction, below the plane with a very different speed in the opposite direction. A particle which happens to be in the plane in question does not move at all. After a long interval the direction of the motions above and below a plane of demarcation may be found to have reversed, respectively. If a solution is cleared of particles by the lapse of a sufficient time for subsidence, they may be restored by brisk rotation. The number, size, density of color and speed of the particle naturally increase with the violence of rotation.

To conclude: After the cessation of the initial disturbances, the liquid, left to itself and owing to the presence of motes, shows a persistent motion of its middle layers in the general direction of the impinging beam of light, while the motion of the relatively thin layers at the top or bottom (one or both) is usually persistently retrograde, but slow in comparison. This continues, until after the lapse of hours the particles have practically subsided, when the retrograde motion seems to be equally prominent. Even when the liquid is manually rotated clockwise with violence, this impressed motion ceases in a few minutes whereupon the counterclockwise, red-blue motion, in the direction of the impinging beam, sets in vigorously.

It suffices to add a few statistical remarks. The telescope may be adapted for small distance by placing 3 diopter spectacle lenses in front of it. Its external focal plane is then only about a foot off and within the liquid. The rays seen in the ocular of the spectrotelescope may be regarded as coming from a virtual slit within the cylinder; or else, on narrowing the incident beam L to within a centi

meter (in case of a cylinder 10 centimeter in diameter), the diffuse internal caustic has already been similarly narrowed down to a short internal spectrum rb in the figure. Hence if the solution rotates slowly about the axis a, particles enter the red (r), and leave the blue (b) end, and are therefore seen sharply in the spectrum travelling from red to violet. The reverse is the case if G rotates in the clockwise sense. The small distance rb is the virtually magnified by the immense dispersion of the grating (15,000 lines to inch) G. Since the rays cross within the cylinder, G, the motion from red to blue will also characterize all particles distinctly seen and rotating counterclockwise. Finally, this rotation corresponds in a general way with the direction of advance of the light transmitted through the cylinder. It would be simplest to refer the cause of persistence to a case of vortical motion in the wake of the beam of light traversing the solution. But the invariable occurrence, in the lapse of time, of motion in the middle layers of the liquid in the direction of the impinging light, no matter how the liquid is artificially rotated in the beginning, leaves this explanation unsatisfactory. Such vortices would not be orderly and persistently equivalent to the effect of a pressure in the direction and of the beam of light. In case of a black body and a solar constant of 3 gram-colories per minute, the energy per unit of volume or the light pressure in question may be roughly estimated at 7X 10-5 dynes per square cm. Even if but a part of the energy is absorbed by the liquid, this is by no means an insignificant pressure in a medium whose internal friction vanishes with its motion. In fact if the given estimate be treated as a tangential force relative to the surrounding dark liquid, of about .01 viscosity, a speed of 7X 10-3 cm./sec. (under normal conditions) would correspond to the shear. One may therefore infer that speeds within a tenth millimeter per second, about of the order observed, are not impossible. The very slow but persistent regressive movement at the top and bottom of the layer of liquid remains unexplained. Furthermore I was unable to find any adequate corre

In

THE thirty-sixth annual meeting of the American Society of Naturalists was held at Johns Hopkins University, Baltimore, December 28, 1918, Vice-president Guy N. Collins in the chair. affiliation with the society at this meeting were the American Society of Zoologists and the Botanical Society of America.

Illness having prevented the attendance of the treasurer the auditing committee was directed to examine his books and report at the next meeting of the society.

The executive committee recommended that sections 1 and 2 of article III. of the constitution be changed to read as follows:

Article III., Section 1. The officers of the society shall be a president, a vice-president, a secretary and a treasurer. These, together with three past-presidents and the retiring vice-president, shall constitute the executive committee of the society.

Article III., Section 2. The president and vicepresident shall be elected for a term of one year, the secretary and treasurer for a term of three years. Each president on retirement shall serve on the executive committee for three years. Each vice-president on retirement shall serve on the executive committee for one year. The election of officers shall take place at the annual meeting of

2 In other words, the conditions of hydrostatic equilibrium imply an inclined surface of the liquid with its maximum head in the region of the illuminated part. But such a structure is gravitationally unstable. It is difficult to see, however, why the flow should be an orderly rotation of nearly the whole cylinder of liquid.

the society, and their official term shall commence at the close of the meeting at which they are elected.

This recommendation was referred back to the executive committee by the society with the suggestion that they consider further the form by which continuity of policy may best be attained.

There were elected to membership: William T. Bovie, Harvard Medical School; Walter B. Cannon, Harvard Medical School; Otto Glaser, University of Michigan; Donald F. Jones, Connecticut Agricultural Experiment Station; Lewis R. Jones, University of Wisconsin; Horatio H. Newman, University of Chicago; Victor E. Shelford, University of Illinois; Theobald Smith, Rockefeller Institute; Alonzo E. Taylor, University of Pennsylvania; Edgar N. Transeau, Ohio State University. The following program was presented: Parthenogenesis and sex determination in the white fly: A. F. SHULL and N. R. STOLL. The evolution of nuclear conditions in Ciliata: M. M. METCALF.

The genetic interrelations of two dwarf perfectflowered types of maize: R. A. EMERSON and S. H. EMERSON. (Read by title.)

Crossing-over and allelomorphism in the grouse locusts: R. K. NABOURS.

The evidence in favor of a linear order of the genes: T. H. MORGAN.

Reversal of dominance in a meal-moth producing some new phenotypic ratios: P. W. WHITING. The globe mutation in Datura: A. F. BLAKESLEE. Some factors in growth correlations: E. W. SIN

NOTT.

On some growth-changes in the body-form of Mellita: W. J. CROZIER. (Read by title.)

The effects of inbreeding on guinea-pigs: SEWALL WRIGHT.

Quantitative relations between chromatin and cytoplasm in the genus Arcella, with their relations to external characters: R. W. HEGNER. (Read by title.)

The Naturalists' dinner was held on the evening of December 28 at the Hotel Emerson with sixtyfive in attendance. Following the dinner Professor A. O. Lovejoy led a round table discussion by members of the American Association of University Professors of the work of certain of its committees. The officers of the society for 1919 are: President-Edward M. East, Harvard University. Vice-president-John H. Gerould, Dartmouth

College.

Secretary-Bradley M. Davis, University of Pennsylvania (1917-19).

Treasurer-J. Arthur Harris, Carnegie Station for Experimental Evolution (1918-20).

Additional members of the Executive Committee-Maynard M. Metcalf, Oberlin, Ohio (1919); Raymond Pearl, Johns Hopkins University (19171919); George H. Shull, Princeton University (1918-20); William E. Castle, Harvard University (1919-21).

BRADLEY M. DAVIS, Secretary

THE AMERICAN FOLK-LORE SOCIETY THE American Folk-Lore Society met in annual session on Friday, December 27, at the Johns Hopkins University. The following papers were read and discussed:

Cape Verde Islands variants of the tale of "the witch and the dogs': ELSIE CLEWS PARSONS, New York.

Ceremonies of the Eskimo of St. Lawrence Island: RILEY D. MOORE, Washington.

The retiring president, C. M. Barbeau, was prevented by illness from attending and delivering the presidential address entitled "The field of European folk-lore in America." The following papers in the absence of the authors were read by title: Resources of Celtic folk-lore in northeast America: EDWARD J. O'BREIN.

Some French-Canadian folk-songs from Gaspé: LORAINE WYMAN.

The officers of the society for 1919 are the following:

President-Dr. Elsie Clews Parsons.
First Vice-president-E. C. Hills.
Second Vice-president—J. W. Fewkes.
Permanent Secretary-Charles Peabody.
Treasurer-A. M. Tozzer.
Editor-Franz Boas.

THE AMERICAN ANTHROPOLOGICAL

ASSOCIATION

THE American Anthropological Association held its sessions on December 27 and 28 at Johns Hopkins University, Baltimore. The Friday morning meeting was devoted to the reading of papers and their discussion as in former years. The following papers were read:

The estimated weight of the parts of the lower extremities in living men: ROBERT BENNETT BEAN, University of Virginia.

The relation of towers to prehistoric Pueblos: J. WALTER FEWKES, Bureau of American Ethnology.

Indian mounds and other relics of Indian life in Texas: J. E. PEARCE, The University of Texas. In memoriam, Herman K. Haeberlin: FRANZ Boas, Columbia University.

In addition to these the following were read by title in the absence of the authors:

Ceremonial objects excavated at Otowi, New Mexico: LUCY L. W. WILSON, Philadelphia. Excavations at Hawikuh, New Mexico, in 1917 and 1918: F. W. HODGE, Museum of the American Indian (Heye Foundation).

Mountain haunts of the coastal Algonquins: MAX SCHRABISCH, Paterson, N. J.

Ethnography of the Jugoslavs: BEATRICE STEVENSON STANOYEVICH, New York.

At the Saturday morning session, papers which had already been published were taken up for discussion. This innovation resulted from the experience of past years, that worth-while discussion of papers, new and just read, was seldom possible.

At the business sessions of the council of the association Professor J. C. Merriam, of the Executive Committee of the National Research Council, presented for discussion a plan for a future permanent research body which should include a division of anthropology. The matter was referred to a committee consisting of Professor Boas, Dr. Hrdlička, and Professor Tozzer, who were directed to present definite research problems of the types most likely to be undertaken and to ascertain the organization best adapted for dealing to advantage with such problems.

The following officers were elected:

President-Clark Wissler, Museum of Natural History, New York.

Vice-president, 1919-John R. Swanton, Bureau of American Ethnology.

Vice-president 1920-George Grant MacCurdy, Yale University.

Vice-president, 1921-A. Hrdlička, U. S. National Museum.

Vice-president, 1922-B. Laufer, Field Museum of Natural History.

Secretary-Alfred M. Tozzer, Harvard Univer

In these waters were laid down thousands of feet of Cambrian and Ordovician sediments which later became the sandstones, limestones and shales now found along the shores of Lake Champlain and for a few miles eastward.

Not long after the close of the Ordovician, metamorphism occurred and the sedimentary beds became mainly schist, slate and gneiss, although there were also quartzite, conglomerate and silicious limestones where the alteration was less complete. The marbles of Rutland County are the result of a somewhat varied phase of this metamorphism, acting chiefly on Chazy and Trenton beds.

Upheaval, folding, faulting and dike intrusion came at this time, as did also the elevation of the present Green Mountains. The sedimentary beds had been laid down before the final elevation upon the eroded and sunken Pre-Cambrian.

Now came an immense interval when, so far as there is any evidence, practically no rock formation occurred in Vermont. There are slight exceptions. A bit of Devonian on the shores of Lake Memphremagog, a trifle of Silurian on the extreme southern border of the state and a larger, but comparatively insignificant belt of Tertiary with its most important outcrop, the Brandon Lignite, are all before the Pleistocene.

What happened during the incalculable time between the Ordovician and the Pleistocene no one knows, but there is no doubt that during this age-long interval erosion beyond imagining must have taken place, and in many respects the land forms were changed.

As is well known, Vermont is decidedly a mountainous state. There is, to be sure, abundance of level ground and good tillable land, but dominating all are the mountains. In single townships there are thirty or forty peaks of noteworthy size and in some instances more than half of these have never been named. In northern Vermont the Green Mountains are somewhat irregularly scattered, but about fifty miles south of the Canadian border they come together in the single range which continues southwards. By this range Vermont

is sharply divided into the eastern Connecticut Valley and the western Champlain Valley.

Any one who journeys through the state finds it easy to pass by good roads from north to south, but from west to east it is often very difficult and in many places impossible. Even politically Vermont has an east and west side, and the very shape of the state is suggested by the presence of this north and south series of mountains.

Naturally, the name of the state recalls only the Green Mountains and certainly the peaks and foothills of this range are by far the most important physical features. On the western border, however, is the not inconsiderable Taconic Range and the series of Sand Rock Hills, while east in the Connecticut Valley are the Granite Hills.

Probably the Taconics were formed somewhat later than the better known Green Mountains. They begin just south of the middle of Vermont and continue, as the Berkshire Hills, into Massachusetts. Though far less important than their larger and more widespread associates, the Taconics are not insignificant. They extend for many miles and include a number of summits over three thousand feet high. Equinox in Manchester is nearly four thousand feet high. In passing through the beautiful valley from Bennington to Rutland the Taconics are conspicuous on the north and the Green Mountains on the south, and the two ranges differ noticeably in outline. The Taconics are largely synclinal in structure, while the Green Mountains are anticlinal or monoclinal. Says Dale in "Taconic Physiography":2

The synclinal mountains must correspond to the original valleys and the anticlinal valleys to the original mountains.

This statement also gives a hint of the great extent to which erosion has taken place in these mountains. This is also shown by the following from the same article:

As the limestone of the valley underlies the schist these valleys must originally have been covered by schist and therefore about half a mile of 2 Bulletin 279, U. S. G. S.