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piece (cylinder, sphere or Bellani plate) is filled with distilled water and the tube is set into the porcelain piece, with the rubber stopper pressed firmly into the neck. The tube is next completely filled with distilled water, by pouring from the reservoir bottle (previously filled), and then it and the porcelain piece together are quickly inverted and the free end of the tube is inserted into the reservoir in the usual manner, the second stopper closing the reservoir.

With the arrangement here described water does not pass downward through the valve, but it readily passes upward, keeping the evaporating surface supplied. This mounting appears to operate perfectly, just as well as do the more complicated forms, it is more easily installed than they, it is easily constructed and the materials are inexpensive and readily obtainable.

BURTON E. LIVINGSTON,
FRANK THONE

THE JOHNS HOPKINS UNIVERSITY

Vernon; First Vice-president, D. W. Morehouse, Drake University, Des Moines; Second Vice-president, R. B. Wylie, State University, Iowa City; Secretary, James H. Lees, Iowa Geological Survey, Des Moines; Treasurer, A. O. Thomas, State University, Iowa City.

The academy ratified the action of its executive committee in accepting affiliation with the American Association for the Advancement of Science, which action had been taken soon after the meeting of the association in St. Louis. The constitution was amended to provide for the collection of dues of the association by the treasurer of the academy at the same time as the academy dues, and also to provide for the beginning of the fiscal year on October 1. Also an amendment was passed providing for the selection by the academy of a representative on the council of the American Association for the Advancement of Science.

The Iowa sections of the American Chemical

Society and the Mathematical Association of America held their meetings in conjunction with the academy.

THE IOWA ACADEMY OF SCIENCE THE thirty-fourth annual session of the Iowa Academy of Science was held in Physics Hall of the State University at Iowa City on April 23 and 24. At the opening session on Friday afternoon, the twenty-third, the memorial portrait of the late Dr. Samuel Calvin, formerly head of the department of geology at the state university and state geologist, was unveiled and presented by the Academy to the State Historical Department at Des Moines. President Stephens then delivered his address on "The Taxonomic Unit."

After the reading of papers the academy adjourned to see the moving pictures showing the University Barbados-Antigua Expedition of 1918 and also those showing the development of the potato disease known as "Leak" by the fungus Pythium DeBaryanum. Owing to the fulness of the program it was necessary to hold a short session after the group dinners, following which President Jessup, of the university, and Mrs. Jessup received the visiting members at their home.

Section meetings were held on Saturday forenoon and at the succeeding business session the following officers were chosen for the coming year: Presi dent, Nicholas Knight, Cornell College, Mount

TITLES OF PAPERS

Botany

The treatment of certain seed-carried diseases: GUY WEST WILSON.

This paper deals with work on cotton diseases conducted by the author and associates at the South Carolina Experiment Station. Cotton anthracnose is the most important disease of field crops in the southeastern states, comparing favorably with the wheat rust in the Mississippi valley. The author and his associates have perfected a method of treating the seed which is practicable on a commercial scale and which bids fair to be of considerable value in the treatment of seed carried diseases of other crops.

Some noteworthy uredinales and ustilaginales: GUY WEST WILSON.

Notes on apogamous Liguliflora: RAYMOND A. FRENCH.

Some aspects of the plant ecology of certain Kansas sand hills: FRED W. EMERSON.

The sand hills studied lie in south-central Kansas along Arkansas river between Wichita and Hutchinson. Dense vegetation holds the sand stable wherever man permits; burning, close grazing and attempts to plant farm crops have removed natural vegetation from considerable areas not only making them useless but threatening neighboring farm lands with being covered with

and Lieutenant Commander Henry B. Soule, United States Navy. A thorough examination was made and the vessel, while showing the effect of active service in which she has been engaged for the past six or eight months, was found to be in good condition and to require a relatively small amount of overhauling. Since the Albatross has been received back from the Navy she has been employed in investigations in the Gulf of Mexico and the Gulf of Maine.

THE Civil Service announces an examination for research engineer. A vacancy at Watertown Arsenal, Watertown, Mass., at $3,000 to $3,600 a year, and vacancies in positions requiring similar qualifications may be filled from this examination. The duties of the appointee will consist of examination of research problems and the design of special apparatus in connection with experiments; submitting reports covering experiments; and, in some cases, putting the recommendations or findings into actual plant operation; also preparing reviews of scientific subjects, including translations from both French and German. The commission also announces an examination for scientific assistant, Bureau of Fisheries, to be held August 4, 1920. From this examination it is hoped to fill several vacancies in the Bureau of Fisheries at basic salaries of $1,200-$1,400 a year. Prospective candidates should apply to the commission for a copy of Form 1312.

A CORRESPONDENT sends us the following letter from Professor P. Rona, of the University of Berlin.

I have recently accepted the editorship of the Zentralblatt f. Physiology, published by Julius Springer. This journal has been organized along the lines of the Chemische Zentralblatt and will take in the entire field of biology. Foreign papers, that is non-German publications, will be given particular consideration.

It would therefore be of extreme importance if I could receive, with your assistance, all the American publications, either in exchange or as reprints, and if necessary through subscription to such journals. The latter, however, would be out of the question for the present on account of the high

rate of exchange. Of equal importance to us would be the reports of the various agricultural and biological stations, etc., which are not available at the ordinary publishers.

A LETTER has been received by the president of Columbia University, from Professor Albert Einstein, of Berlin University, thanking the trustees of the university for the Barnard Medal, conferred on him at this year's commencement on nomination of the National Academy of Sciences "in recognition of his highly original and fruitful development of the fundamental concepts of physics through application of mathematics." The letter says: "I beg to express to you my glad thanks for the great honor which you propose to do me. Quite apart from the personal satisfaction, I believe I may regard your decision as a harbinger of a better time in which a sense of international solidarity will once more unite scholars of the various countries."

DR. THOMAS P. FOLEY, chairman of the contract practise committee of the Chicago Medical Society, has started a movement among the members of the society to organize a union and has made the following statements:

Why should a physician, who has studied for years to perfect himself for his work, be paid less than an unskilled laborer? Yet it is the rule rather than the exception.

Recently a physician giving full time to industrial surgery in a large Chicago plant, rendered first aid to a man working as an unskilled laborer. The physician received $75 a month with room and board. The laborer's pay check for one week, which he showed the physician, was for $80.

Take the state service for example. At the Dunning Hospital for the Insane the chief electrician stands next on the pay roll to the superintendent. His salary is $265 a month. That of the highest paid physician on the staff is only $245. The electrician is a union man. The physician has no organization back of him.

We propose to form an organization along semiunion lines in Chicago like the lawyers' association and other such bodies of professional men. It is not aimed at the public, but rather at industrial and other corporation employers of physicians.

UNIVERSITY AND EDUCATIONAL

NEWS

OHIO STATE UNIVERSITY has received a gift of $400,000 by Charles F. Kettering, a trustee of the university, for medical research in connection with the college of homeopathy.

W. A. CLARK, JR., of Butte, Montana, has presented a fund of $4,000 to the geological department of the University of Wisconsin for the purchase of equipment for experimental work in structural geology.

THE University of Wisconsin has obtained legal authority to offer a complete four year medical course.

DR. CHARLES B. FULTON, of Cleveland Ohio, has been appointed a director of the School of Mines and Metallurgy, Rolla, Mo.

DR. EMERY R. HAYHURST, professor of hygiene at Ohio State University, has been made head of the department of Public Health and Sanitation and Mrs. Norma Selbert, formerly of the University of Missouri, has been appointed assistant professor of public health nursing.

DR. W. THURBER FALES, of Malden, Mass., has been appointed instructor in biology and public health in the medical school of the Johns Hopkins University.

DR. V. J. HARDING, associate-professor of biological and physiological chemistry at McGill University, has been appointed professor of pathological chemistry in the University of Toronto.

DR. DOWELL YOUNG, of Cornell University, has been appointed professor of biology in Dalhousie University, Halifax, in place of Professor C. Moore, resigned.

AT the University of Leeds Dr. W. E. S. Turner has been appointed professor of glass technology, Mr. J. Husband professor of civil engineering and Dr. Mellanby professor of pharmacology.

DISCUSSION AND CORRESPONDENCE
THE RESCUED FUR SEAL INDUSTRY
AT the St. Louis fur auction held on Feb-
ruary 2, 1920, there were sold for the United

States government 9,100 skins of fur seals, the net proceeds of which were $1,182,905, an average of $140.98 per skin.

That sale marks an important period in the history of the most practical and financially responsive wild life conservation movement thus far consummated in the United States. In 1911 one of the stakes set by the advocates of the five-year close season was a return to a revenue of at least "$1,000,000 per year," and now it is no exaggeration to say that the results of the long close season that began in 1912 and ended in 1917 have been everything that the close-season advocates claimed that they would be.

The steady and very rapid increase in the fur seal population of the Pribilof Islands during their five years of immunity from commercial slaughter is revealed by the following official census figures as made by the United States Department of Commerce, and kindly furnished by Secretary Alexander.

In 1912 there were 215,738 seals of all ages. In 1913 there were 268,305 seals of all ages. In 1914 there were 294,687 seals of all ages. In 1915 there were 363,872 seals of all ages. In 1916 there were 417,281 seals of all ages. In 1917 there were 468,692 seals of all ages. In 1918 there were 496,432 seals of all ages. In 1919 there were 530,237 seals of all ages.

The total number of fur seals killed for their skins since the open season began have been as follows:

In 1918 the number was 34,890. In 1919 the number was 27,821.

The prices realized at the St. Louis fur auctions on the sale of fur seal skins are revealed by these figures:

In 1918 there were sold 8,100 skins for $375,385. Average, $46.34 per skin. In 1919 there were sold 19,157 skins for $1,501,603. Average, $78.38 per skin. In 1920 there were sold 9,100 skins for $1,282,905. Average, $140.98 per skin. If the average price of $140.98 at which the lot of 9,100 skins sold on February 2, 1920, should hold for the entire

catch of 27,821 skins taken in 1919, the total gross revenue for the lot would be $3,922,204.58.

In view of the feverishly advancing prices of all kinds of real fur, the growing scarcity of the supply, and the clamorously insistent demands, both of the rich and the poor, there are good grounds for the belief that very soon we will see good raw fur-seal skins selling at auction at an average price of $250 each. With 110,000,000 people in America demanding "fur," the future of the trade in real fur is remarkably bright-so long as the supply lasts -and Congress may regard the future of the nation's fur seal industry with entire complacency. The saving of the fur seal herds was a good investment.

In the future, when all other bearers of good fur have been utterly exterminated-as they soon will be-the protected fur seal herds will produce, by sure-and-certain arithmetical progression, a really vast quantity of the finest fur in the world. It needs no stretch of prophecy to foretell the annual increment to the three nations who now are so sensibly preserving the fur seals of Alaska from killing at sea. When we begin to take, as we formerly did in the days of the fur seal millions, an annual catch of 100,000 skins, the importance of the salvaged fur-seal herd will be realized. If we figure it out on a basis of the sale of February 2, 1920 at St. Louis, the answer is $14,098,000 per year, 75 per cent. of which will belong to the United States.

Under the terms of our treaty with England and Japan we are dividing net proceeds with those two partner nations, who now help us to preserve the fur seals when at sea, on the perfectly fair basis of 15 per cent. to Japan, and 10 per cent. to England. During the five-year closed season we annually paid to each of those two nations the sum of $10,000.

In its habits the fur seal-which in reality is not at all a true seal, but a fur-coated sealion-is one of the most remarkable of all sea-going mammals. There are writers who still insist that fur seals can be managed by man just as a farmer manages his herds of

breeding cattle and horses. As a matter of fact, the fur seal is hopelessly wild and untamable, and the only "management" that man can bestow upon the free animal is in terms of slaughter. He can drive it and kill it by artificial or by natural selection, but that is absolutely all. The fur seal migrates, returns, breeds and feeds solely in accordance with its own erratic and persistent will, and man's so-called "management" lies solely in the use of the seal-killer's club and the skinning-knife.

NEW YORK

WILLIAM T. HORNADAY

SIDE-TO-SIDE VERSUS END-TO-END CONJUGA-
TION OF CHROMOSOMES IN RELATION
TO CROSSING OVER

THE stonefly, Perla immarginata Say, is exceptionally fitted for chromosome studies as it has only five pairs (including the X-Y pair) of chromosomes, each pair of which is structurally differentiated from all others. My observation on this form made in 1917-18 forced me to the conclusion that in the prophase of the first spermatocytic division 66 homologous chromosomes are connected to each other telosynaptically in the spireme," and later "they bend toward each other at the synaptic point and become reunited parasynaptically before metaphase." These conclusions are in agreement with a limited number of workers but are so opposed to the general contention of the majority of cytologists to-day that it was considered then unprofitable to do anything more than describe the process as observed. This was done in my previous paper in the Journal of Morphology, in which no attempt was made at theoretical discussion in relation to certain genetical evidences.

As so convincingly summarized in Morgan's recent book, Mendel's original law-the segre

1 Nakahara, W., "A Study on the Chromosomes in the Spermatogenesis of the Stonefly, Perla immarginata Say, with Special Reference to the Question of Synapsis, Jour. Morphol., Vol. 32, 1919.

2 Morgan, T. H., "The Physical Basis of Heredity," 1920.

gation and independent assortment of factors -has been shown to have a close parallelism with the actual behavior of the chromosomes. The situation is quite otherwise, however, as to the mechanism of crossing over. Morgan is right when he states that "while the genetic evidence is favorable in all essentials to the theory of interchange between homologous chromosomes, it must be confessed that the cytological evidence is so far behind the genetic evidence that it is not yet possible to make a direct appeal to the specific mechanism of crossing over on the basis of our cytological knowledge of maturation stage." Morgan, however, assumes the side-to-side conjugation as a fact. His analysis of data on parasynapsis leads him to the conclusion that the early thin thread stage is most favorable for crossing over to take place. End-toend conjugation, or telosynapsis, according to Morgan, "would have serious consequence for genetics. . ., for while side-to-side union offers an opportunity for interchange between the paternal and maternal members of a pair, no such interchange could be postulated if end-to-end conjugation took place."

It is the purpose of the present note to emphasize that the process of end-to-end conjugation, at least as described by Nothnagel3 for a botanical object, and by myself1 for a zoological one, does offer an opportunity for crossing over to take place, contrary to Morgan's statement. End-to-end conjugation simply restricts the stage in which such an opportunity is offered. This can be readily seen from the works of the above-mentioned authors, who describe essentially the following process:

A separate loop or segment of double spireme, whatever the nature of its duality may be, gradually bends and halves of the loop come to lie closely side by side. In the tetrad thus formed there are four longitudinal strands or threads.

It will be seen, then, by telosynapsis, an opportunity is offered for interchange between

Nothnagel, M., "Reduction Division in the Pollen Mother Cells of Allium tricoccum," Bot. Gas., Vol. 61, 1916.

chromosomes at the thick thread stage, but at this stage only, in the manner originally suggested by Janssen in his chiasma type

It must be remembered that the condition of the chromatin threads at the early stage when the double spireme develops is extremely difficult to study minutely and accurately with the method and apparatus at our command. Under such circumstances, any inclination on the part of the observer will have a considerable influence on the interpretation. If one is so disposed, he may consider the condition of the threads as representing the process of pairing up. Dual threads develop out of reticulum at this stage, and that was all I could be sure of. There was certainly no observable evidence of the process of pairing up of two simple threads at least in the stonefly I studied.

On the contrary, the formation of a tetrad or ring by the bending of a loop of double spireme, which appear in haploid number is a clearly demonstrable fact. It is from this ground that I interpret the haploid as being composed of two homologous chromosomes jointed up end-to-end, and its duality as indicating primary splitting. No one has ever seen two chromosomes actually coming into conjugation, but the subsequent bending, reconjugation in side-to-side position, and the ultimate segregation at metaphase, of the halves of the loop is explicable only under the assumption that two chromosomes were united end-to-end in the loop.

Whether I am right in this interpretation or not will be decided by future studies-perhaps in very near future. Detailed comparison of the premeiotic stage with the prophase of somatic mitosis would throw some light on the situation. Also, a careful re-examination of forms (Orthoptera, for instance), in which parasynapsis is customarily claimed to occur, with special reference to the haploid loops in the thick thread stage would help settle the question. Possibility no doubt exists that the

Janssen, F. A., "La théorie de la chiasmatypie. Nouvelle interprétation des cinèses de maturation," La Cellule, T. 25, 1909. theory.

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