the following officers were elected: President, Sir Robert Hadfield, Bart., F.R.S.; Vice-presidents, W. R. Bousfield K.C., F.R.S., Professor F. G. Donnan, F.R.S., Dr. Eugene Haanel, Professor A. K. Huntington, Dr. T. Martin Lowry, F.R.S., Professor Alfred W. Porter, F.R.S.; Treasurer, Robert L. Mond; Council, G. S. Albright, W. R. Cooper, Dr. C. H. Desch, Dr. J. A. Harker, F.R.S., Emil Hatschek, Cosmo Johns, Harold Moore, E. H. Rayner, Dr. George Senter, Cav. Magg, E. Stassano. Ar the annual meeting of the Washington Academy of Sciences held at the Administration Building of the Carnegie Institution on January 14, 1919, the retiring president, Dr. Lyman J. Briggs, delivered an address on "The resistance of the air." A JOINT meeting of the Washington Academy of Sciences and the Chemical Society of Washington was held on January 9, when Dr. F. B. Power, retiring president of the Chemical Society, delivered an illustrated address on "The distribution and character of some of the odorous principles of plants." THE annual Darwin Lecture of New York University will be given on February 12 by Dr. C. L. Bristol, of the department of biology. In connection with the lecture a series of motion pictures of marine life made in Naples, Italy, will be shown by Dr. R. L. Ditmars, curator of reptiles, New York Zoological Gardens. A CABLE message announces the death in Rome, on December 31, of David Lubin, of San Francisco, founder of the International Institute of Agriculture, and the American representative on its permanent board. He was born in 1841, and was formerly a merchant in Sacramento, where early in his career he made a fortune. He then devoted himself to economic reforms and was responsible for the establishment at Rome of an international agency for collecting official and reliable information from all parts of the world as to the acreage, output and ability of the cereal crops. THROUGH an anonymous donor The Long Island College Hospital (Hoagland Labora 1 tory) has had placed at its disposal a farm for keeping animals used in research. Already work and experimentation in fowl influenza (roup), diphtheria and chicken-pox have been begun. UNIVERSITY AND EDUCATIONAL PROPOSALS for extending the accommodation and equipment of the department of pathology and bacteriology at Leeds University have been approved. It is hoped to concentrate the whole of the bacteriological work of the city in the additional accommodation provided by adapting the premises adjacent to the medical school. THE Massachusetts Institute of Technology plans to offer to students who have substantially completed courses leading to the degree of bachelor of science in chemistry or chemical engineering, an opportunity to enter the school of engineering practise in February. Two terms of preparatory work will be given at Cambridge, the first beginning February 17; it is expected that the work at the practise stations will begin about October 1, and continue until the following May. The general plan of the course will be the same as that carried out while the school was in operation just before the opening of the war. THE REV. EDWARD P. TIVNAN, S.J., professor of chemistry and regent of the school of medicine, Fordham University, has been appointed president of the university, to succeed the Rev. Joseph A. Mulry, S.J. THE departments of descriptive geometry and mechanical drawing and of mechanism and machine design at Stevens Institute of Technology have been combined to form a new department of machine design, of which Franklin DeR. Furman is professor and head. The work of the department has been organized with two divisions-one the mechanism division, in which William R. Halliday is assistant professor, and the other the mechanical drawing division, in which Edwin R. Knapp is professor and Samuel H. Lott, assistant professor. The following changes in rank have been made at the institute: Louis A. Hazeltine, acting professor in the department of electrical engineering, to professor; Robert M. Anderson, acting professor in the department of engineering practise, to professor; Lewis E. Armstrong, instructor in the department of mathematics, to assistant professor. MR. LESTER YODER, formerly with the chemical section of the Agricultural Experiment Station of Iowa State College, is now at the U. S. Technological School, Carney's Point, N. J. THE chemistry department of the University of Nebraska announces the following additions to its teaching staff: Dr. Horace G. Deming, of the University of Illinois, as professor of chemistry in charge of general and physical chemistry; Mr. B. Clifford Hendricks, of Peru, Nebr., State Normal School, as assistant professor of chemistry; Mr. T. J. Thompson, of Kansas Wesleyan University, as instructor in organic chemistry. DISCUSSION AND CORRESPONDENCE THE LILLE SOCIETY OF SCIENCES TO THE EDITOR OF SCIENCE: I wish to call the attention of American scientists to the following extracts from a letter received from Dr. Charles Barrois, professor of geology at the University of Lille and actively interested in the Society of the Sciences of Lille. Dr. Barrois writes: For four years I have been cut off from the number of the living, reduced to servitude, without receiving a letter or a scientific book; I have not been able during this time to communicate with anybody in the world, nor to have any news of my family. That has been harder to me than physical sufferings and bombs. My geological institution has been twice demolished by bombs, but I was able to save the collections from the débris and they were respected by the Germans. Our library of the Society of Sciences was unfortunately burned so that I am much embarrassed in my work; the books of the Public Library were also burned, those of the university were saved, but that was the least important library. I am working at present to build up again my university, our Geological Society of the North, all the members of which are scattered, ruined or killed. I do not yet know if I shall succeed; books are necessary, and money is necessary to continue my publications and I fear it can not be obtained in France where they are much impoverished. I look sadly at the manuscripts of my confrères, entrusted to my care for publication. . . . I am quite a little disconcerted at being reduced to mendicancy in my old days, for our learned societies, but the American devotion and generosity have been shown so great in these latter days, that we believe we can be assisted by them openly. If any one has any books or specimens that they think would be of assistance to Dr. Barrois and his associates in connection with the Library and Museum of the Society of the Sciences, the Smithsonian Institution will be very glad to transmit them to the society at Lille. CHARLES D. WALCOTT ROOT PRESSURE AND ROOT EXUDATION A RECENT note in SCIENCE by Professor Kremers1 upon the use of dahlias for experimental work upon osmosis reminds the writer of his use of the same plant for the demonstration of root pressure and the exudation of water in quantity. The growth from the tuberous roots is vigorous and in a short time is ready for the setting up of the experiment. The quantity of water exuded and the pressure are adequate for a thorough demonstration of these phenomena as outlined for example in Ganong's "Plant Physiology" and fully equal to the best plants which the writer has used in such demonstrations. In this connection the writer wishes to express a thought which has been more and more impressed upon him in his work as a teacher of physiology, pathology and even morphology of plants. Each institution, and especially is this true of the smaller ones, is working out its technical problems in an isolated fashion, often repeating unprofitable experiments which have been found by other institutions to be unsuccessful. In other cases especially useful plants or types of ap 1"Experimental Osmosis with a Living Membrane," Edward Kremers, SCIENCE, N. S., Vol. XLVIII., No. 1250, December 13, 1918, p. 599. paratus are in use, the knowledge of which would be of great value both as time savers and as means of encouraging better teaching of botany. Why should there not be a free exchange of such methods and ideas through the medium of publication in one of our universally distributed journals such as SCIENCE? The writer suggests a special department, in such a magazine, devoted to technique where not only successful experiments in teaching are reported but also where negative results shall be stated. A magazine devoting space to such a department would do much toward advancing the technique of science. It may be objected that such notes do appear from time to time in various magazines. This is true, but the writer is convinced that only a very small number of such notes appear as compared with the total number of helpful suggestions which should be the common property of men working in the same science. In this branch of educational work at least there should be no selfish "patent" upon such matters to be used as a 66 drawing card" for the department or institution. Such a department devoted to notes upon technique would save all teachers of science much time which they now spend in fruitless testing out of methods which some other institution has already demonstrated to its own satisfaction to be unsatisfactory. There would also be a marked improvement in the teaching in the smaller institutions at least, by the introduction of newer and better technique. ERNEST SHAW REYNOLDS AGRICULTURAL COLLEGE, N. D. GENERIC LIMITATIONS THE deductions of Professor Robertson on this subject in SCIENCE for October 11 seem to be based upon questionable premises. Of the factors which influence the number of species in a genus, he mentions only the antiquity of the group. Other important factors are: specific limitations; size of group considered; area, location and diversity of territory included; degree of perfection of our knowledge of the species. These are illustrated in the following list: ! Species Genera Cat. N. Am. Pl., Heller, 19001 16,673 R. Mt. Fl., Rydberg, 1918.. Pl. of Conn., 1910.. Bees of N. Mex., Ckll., 1906 2,733 5,897 2,912 702 4.2 4.7 2,903 1,942 1,746 554 3.2 4.2 963 448 2.2 3.1 It will be noted that the averages vary in proportion to size and diversity of territory. On account of this and narrow specific limits Rydberg's "Rocky Mountain Flora" is one of the highest, notwithstanding his narrow generic limits. New Mexico runs low on account of many Mexican genera entering the state. Since the bees are but a suborder we may scarcely compare them with larger groups. The Poales are perhaps the most nearly comparative group of the plants, although relatively larger. The genus Carex is more nearly comparable than any other to the bee genus Andrena, the number of species being about equal. From Robertson's list we find the bees of New Jersey are 2.7 per cent. of the total insect list, while those of Carlinville are 23.0 per cent.; similarly, the Lower Aculeata are 4.9 per cent. and 16.2 per cent. From this and our knowledge of the extent of his work on these groups we might conclude the averages for other groups to be low on account of their many unknown species. Recognition of many small genera would seem to necessitate the elevation of old genera and larger groups to higher rank, thus greatly increasing group names. Classification serves two purposes. Names have been often called "handles," while the system presents the state of our knowledge of relationships. For the 1 Includes varieties; others do not. taxonomist, large numbers of names present little difficulty because he uses them frequently, but for others it is different. Thus probably not less than 90 per cent. of science workers are "beginners" and the others, outside of their special fields, are also. The writer believes in the recognition of small groups but doubts the necessity of forcing them upon every one. our floras and faunas in two parts, the first leading to collective groups, the second continuing through the smaller groups? Would it not be feasible to have AGRICULTURAL COLLEGE, NORTH DAKOTA O. A. STEVENS FIREFLIES FLASHING IN UNISON TO THE EDITOR OF SCIENCE: I was much interested in Mr. Fremont Morris's letter regarding the "Fireflies Flashing in Unison" on page 418 of the last volume. I was employed by the Philippine Bureau of Forestry during 1902 and 1903. In the spring of 1902, I was stationed for some weeks at Pagbilao, Tayabas Province. It is on a small tidewater river about half or three quarters of a mile from Lagimanoc Bay. I had occasion to go across this bay on February 22 and did not return until after dark. As the banca in which I was travelling entered the mouth of the river, I was attracted to the flashing of the flies which appeared in great numbers a short distance above the mangroves which covered both banks of the stream. The majority of the fireflies were flashing in unison but there were some which did not time their flashes with the majority. The light from the fireflies with the reflection of the light from the water made a very distinct illumination and one never to be forgotten by one who has seen it. P. T. BARNES PENNSYLVANIA DEPARTMENT OF AGRICULTURE NEGATIVE RESULTS FROM ATTEMPTED QUEEN BEE MATING IN A DOUBLE TENT INCLOSURE FOLLOWING Out suggestions from previous work of Cole and Miller, Rhode Island, and from bee behavior observations in an artificially lighted double tent at University of Wis consin, by the writer, an attempt was made the past season to mate a Virgin queen bee in an available double tent inclosure. The tent was made of double canvas, 4 feet in diameter, 7 feet high at peak, with about 8 inches space between the canvas walls. A nucleus, containing workers, drones and a five-day-old virgin was placed in the tent and observations taken. No natural mating flights occurred. The virgin appeared to fly naturally in the tent, returning unaided to the hive, when removed from the nucleus and thrown into the air. The drones appeared to fly naturally, more so at first than after several days confinement in the tent. The queen failed to mate. L. V. FRANCE UNIVERSITY OF MINNESOTA, UNIVERSITY FARM, ST. PAUL SPECIAL ARTICLES SPECTRUM PHENOMENA DUE TO MOVING MOTES IN connection with my regular work I incidentally came upon a curious phenomenon which seemed to repay special investigation. To describe it, it will be advantageous to first indicate the disposition of apparatus used, as is done in Fig. 1. Here L is a pencil of white light (preferably from a collimator and wide slit) impinging on the thin cylindrical glass shell G, about 10 cm. in diameter and containing a solution of mercury-potassic iodide, about half an inch deep and not quite concentrated. The rays are thus both refracted and dispersed, and on emerging enter the strong objective of a short-range telescope (magnification above 15) of which PP' is the principal plane and r'b' the narrow spectrum seen in the ocular of the telescope. Properly focusing the latter, the spectrum may be contracted to a vividly colored vertical line. If now a strong direct-vision grating g is inserted in front of the objective, and the telescope is focused anew, a sharp solar spectrum may be obtained. This was a surprise to me, as the cylinder1 G, though thin and clear, was 1 The present use of a cylinder as a collimator is well worth noting. obtained from samples of ordinary glass shades, such as are prized by the lovers of stuffed birds. In other words, the cylinder supplies its own slit within, as at r or b in the figure, by refraction. With a narrow beam of sunlight no collimator is needed. The spectrum will now be found to be filled with short, slender, horizontal shadows moving endwise in a common direction, but at different speeds. On pushing the ocular in somewhat further, these shadows become sharply defined lines, all nearly horizontal, of all lengths from mere points to black lines half the length of the spectrum or more. On attentive observation the black lines are seen to ing intersected with an interminable array of slow horizontally flying arrows, shot in a common direction from end to end. With regard to the motion, this is more usually horizontally from red to blue; in the lapse of time and in the middle layers always so and not permanently from blue to red. Sometimes both motions were seen to occur together in different levels, the retrograde motion being relatively slow, less pervasive and confined to the top or the bottom layers of the liquid. All degrees of speed occurred from a passage through the spectrum in a fraction of a second, to passages lasting over a minute. Under the latter conditions it may happen that the particles actually stop and then begin a retrograde movement soon to be accelerated in turn. During this period of transition, particles may be seen also to rise and fall, but with relatively great slowness as compared with the usually horizontal motion. Some of the arrows are somewhat oblique to the horizontal. Under rare conditions I noticed a line of light instead of shadow. Breadths differ greatly and would naturally depend on focusing. Usually the motion persists with apparently undiminished small velocity for hours, so that it much outlasts one's patience. Often a single particle can be observed for a minute or more; but after 10 or 20 hours all particles disappear and the spectrum is clear. From this I concluded that the diffractions are not due to local difference of density, etc., of the solution, as I first supposed, but actually originate in minute solid particles (or in case of other liquids in minute air bubbles) entrapped in the liquid. The slow subsidence and persistence of particles indicates this state of things. Moreover I found that the initial motion of particles as a whole from red to blue or blue to red, could be controlled by rotating the cylinder G on its axis a, either counter-clockwise or the reverse, respectively. Brownian motions are excluded, since these are promiscuous and since the magnification is inadequate. It is difficult to conceive how the angular momenta impressed on this solution can persist for hours within it, after the solution is apparently quite at rest, even if the solution is of large |