the study of such large cells as the amphibian chromatophores a much more satisfactory microscopic preparation may be obtained by mounting pieces of skin entire.

During the course of experimental studies on the relation of certain of the endocrine glands to pigmentation and growth changes in the frog, striking objective proof has been obtained that the "silvering" which follows hypophysectomy is due mainly to contraction of certain melanophores and not to any marked reduction in the amount of pigment material present.

The experiments to be described were performed upon larvæ of Rana sylvatica. This frog is very darkly pigmented in young stages and the "silvering" which follows hypophysectomy is consequently a very striking color change. The hypophysis was removed, following the methods of Allen and of Smith, at a stage just preceding the appearance of muscular activity. The operated larvæ were immediately returned to large crystallizing dishes containing city water (Ann Arbor, Mich.). Although this water is very hard and may contain traces of chlorine, there was not the high mortality among operated tadpoles which Allen noted. The characteristic silvering appeared from the eighth to the tenth day following the operation. As noted by the previous observers mentioned the operated larvæ were constantly smaller than controls of the same age and were somewhat more active.

.

When a length of from 12 to 14 mm. had been attained groups of the silvery larvæ were placed in a dilute extract of pars intermedia of beef pituitary or in an emulsion made by shaking a few mgm. of dried pars intermedia in 100 c.c. of distilled water. For each experiment a control group of larvæ was placed in an equal amount of distilled water. The larvæ placed in contact with the pars intermedia substance soon underwent a striking change from silvery to dark, in which condition they closely resembled the normal tadpole. This change began to be apparent in 15-30 minutes and attained a maximum in from one to three hours, depending on the

strength of the extract or emulsion employed. When returned to fresh water the darkened larvæ soon regained their silvery appearance (one to three hours).

This experiment proves conclusively that the silvery appearance of the hypophysectomized larvæ is not due primarily to a loss of pigment substance. It indicates rather that it is due to a sustained contraction of pigment-bearing cells, which may be caused to expand again by suitable stimuli.

To test the validity of the latter assumption the experiment was repeated with the larvæ held in Clarke's observation chamber so that changes in the pigment cells could be watched under the microscope. In silvery larvæ the sub-epidermal melanophores were found to be contracted into dense spherical masses, whereas in normal larvæ the same cells were greatly expanded so that processes of neighboring cells were almost in contact. When a silvery larva was subjected to the action of an extract of pars intermedia the contracted pigment cells were seen to expand slowly. In one experiment a definite change in the cell under observation could be noted within eighteen minutes. The cell continued to expand slowly by sending out pseudopodia-like processes into which pigment granules could be seen to stream.

To further elucidate the nature of the pigment change toto mounts of pieces of skin stripped from normal and experimental larvæ after fixation in Bouin's fluid, were prepared. as follows: (a) normal, (b) silvery (hypophysectomized), (c) darkened silvery (hypophysectomized, under influence of pars intermedia extract).

contracted, some completely so that they form dense spherical masses; others are only partially contracted. This is in accord with what may be observed in the tail of the living silvery tadpole. Another feature which immediately attracts attention is the apparent absence of the epidermal melanophores. Upon closer examination the faint outlines of a few such cells may be made out. The cells contain very few pigment granules. Whether the remaining cells have migrated from the epidermis to deeper parts, as stated by Allen, or whether they have become invisible from loss of pigment granules could not be determined. It is apparent, however, that those occasional epidermal melanophores which may be identified contain only a small proportion of the number of pigment granules to be found in the normal condition. Whether the pigment granules have been changed and absorbed or have left the melanophore to become more widely distributed likewise has not as yet been established.

When a silvery larva has been darkened by the action of an extract of pars intermedia the sub-epidermal melanophores are found to be expanded, thus approximating the normal condition. The epidermal pigment cells, however, are not restored.

It may be concluded, then, that the change in color which follows hypophysectomy in the frog larva is due primarily to a contraction of the sub-epidermal melanophores. Only secondarily is it due to a loss of pigment granules from certain of the epidermal melanophores, and to a possible migration or loss of other epidermal melanophores.

WAYNE J. ATWELL

DEPARTMENT OF ANATOMY, UNIVERSITY OF BUFFALO

THE PALEONTOLOGICAL SOCIETY THE Paleontological Society held its tenth annual meeting at Baltimore, December 28, 1918, meeting in affiliation with the Geological Society of America. The meeting was held in the civil engineering building of Johns Hopkins University, with an attendance of about forty members and visitors. Following the business session and the

presentation of appreciations of the life and work of four deceased members, the reading of papers bearing upon the various branches of paleontology and stratigraphy was commenced and continued until late in the afternoon. In the evening the members attended the annual dinner with the Geological Society of America at the Southern Hotel.

Of special mention among the papers presented, listed below, was the address of the retiring president, Dr. F. H. Knowlton, on "The evolution of geologic climates," in which the evidence of paleobotany was the predominant theme, and the papers on the Philosophical Aspect of Paleontology and the Economic Value of the Science. Important stratigraphic and paleontologic results were announced by the members particularly regarding the Coal Measures of Maryland, the Oxfordian of Cuba and the Tertiary rocks of South America. The following papers were read:

Paleontologic Papers

Relation of the Holochoanites and the Orthochoanites to the Protochoanites, and the significance of the Bactritida: AMADEUS W. GRABAU. On the inclusion of the Pleistocenic period in the Psychozoic Era: AMADEUS W. GRABAU.

The philosophical aspects of paleontology: JOHN M. CLARKE.

Characters and restoration of Cope's Sauropoda: HENRY FAIRFIELD OSBORN.

Camarasaurus and Amphicalias from Canyon City: HENRY FAIRFIELD OSBORN and CHARLES C. MOOK.

Orthogenetic development of the costa in the Perisphinctina: MARJORIE O'CONNELL.

Discovery of the Oxfordian in western Cuba: BARNUM BROWN and MARJORIE O'CONNELL. A new Eurypterid horizon: GEORGE H. CHAD

WICK.

The economic value of paleontology: RALPH ARNOLD.

Stromatopora growth on edgeon conglomerates from the Silurian: JOHN M. CLARKE.

Stratigraphic Papers

The age of certain plant bearing beds and associated marine formations in South America: EDWARD W. BERRY.

The stratigraphy and correlation of the coal measures of Maryland: CHARLES K. SWARTz, W. A. PRICE, JR., and HARVEY BASSLER.

The typical section of the Allegheny formation: CHARLES K. SWARTZ and HARVEY BASSLER.

The Eocene divisions of California: BRUCE L. CLARK.

Some problems of the Adirondack Precambrian : HAROLD L. ALLING.

Permo-Triassic of northwestern Arizona: HARVEY W. SHIMER.

The stratigraphy and structure of the Newark system in Maryland and its relation to the Newark system of eastern North America: GEORGE EDWIN Dorsey.

THE American Psychological Association held its twenty-seventh annual meeting at Johns Hopkins University on December 27 and 28. Considering the fact that many of the members made other plans when it was announced in November that there would be no meeting, the sessions were very well attended, there being about seventy members present. Owing to illness the president, Professor J. W. Baird, of Clark University, was not able to preside nor to give his presidential address.

The papers consisted with one exception of descriptions of the war activities of the members. The program was as follows: Research in psycho-pharmacology, Dr. David I. Macht; Study of ocular functions with special reference to aviation, Professor C. E. Ferree; Revision of the definition for "moron "; Captain R. L. Sylvester; Psychology of morale, Major Wm. S. Foster; Selection and training of telegraphers, Professor L. L. Thurston; Some problems of reeducation, Professor S. I. Franz; Principles underlying the classification of men in the Students' Army Training Corps, Professor T. L. Kelley; Examination of the emotional fitness for warfare, Professor R. S. Woodworth; Practical application of army trade tests, Major J. W. Hayes; Army personnel work: implications for education and industry, Lieutenant Colonel W. V. Bingham; The work of the psy

chological committee of the National Research Council and of the Division of Psychology, Major R. M. Yerkes; Methods of mental testing used in the United States Army, Major Lewis M. Terman; Psychological service in army camps, Major George F. Arps; Results and values of psychological examining in the United States Army, Dr. Mabel R. Fernald; The relation of intelligence to occupation as indicated by army data, Dr. J. W. Bridges; Some possible effects of the war on American psychology, President G. Stanley Hall; Functions of psychology in rehabilitation of disabled soldiers, Major Bird T. Baldwin; A program for mental engineering, Lieutenant Commander Dodge; Official method of appointing and promoting officers in the Army, Colonel Walter Dill Scott; Psychological investigations in aviation, Major Knight Dunlap; Speech reconstruction in soldiers, Professor W. B. Swift.

Saturday afternoon there was a symposium upon "The future of pure and applied psychology." Professor Thorndike expressed the opinion that in twenty years there would be as many "doing" as teaching psychology, but that both groups must be thoroughly scientific. He saw no reason why the Ph.D. degree in psychology should not represent both types. President Hall stated that psychology should be kept pure, but not so pure that it could not be helpful. Its motto should be "service" in the best sense of the term. Major Yerkes discussed the future relation of psychology to a permanent National Research Council.

Professor E. L. Thorndike, as the retiring vice-president of Section H of the American Association for the Advancement of Science, delivered an address upon Scientific personnel work in the army" and Professor E. F. Buchner as retiring vice-president of Section. L of the American Association for the Advancement of Science spoke upon "Scientific contributions of the educational survey."

A brief report of the contents of all the papers will be made in the February number of The Psychological Bulletin.

Colonel Walter Dill Scott was elected president of the association for 1919 and Major Bird T. Baldwin and Major Lewis M. Terman members of the Council.

HERBERT SIDNEY LANGFELD

Secretary

THE OPTICAL SOCIETY OF AMERICA THE third annual meeting of the Optical Society of America was held under the auspices of the American Association for the Advancement of Science in Baltimore, December 27. The program consisted of the scientific papers listed below with a Symposium on The Future of Applied Optics and a business meeting.

MORNING SESSION, 9:30

The colorimetry of white surfaces: A. P. PFUND. The measurement of reflection and transmission factors: M. LUCKIESH.

The design of lenses for aerial photography and tests of calcium as a desiccator in optical instruments: C. W. FREDERICK.

Retinal fatigue for luminosity with spectral stimuli: L. T. TROLAND.

A new yellow dye and light filters made from it: C. E. K. MEES and H. T. CLARKE.

The contraction of photographic images: F. E. Ross.

Refinements in spherometry: G. W. MOFFITT. The problem of magnification in fire control instruments, and The transmission of certain glasses in the absorbent region: E. D. TILLYER.

A possible new lens material: P. G. NUTTING. A chart method of testing photographic lenses: L. E. JEWELL.

Monocular vs. binocular field glasses: E. P. HYDE and COMMITTEE.

A testing apparatus for stereoscopic vision: H. KELLNER.

A one-term pure exponential formula for the spectral distribution of radiant energy from a complete radiator: I. G. PRIEST.

Photoelectric spectrophotometry by the Null method: K. S. GIBSON.

The protection of silvered surfaces: F. L. G. KOLLMORGEN.

The proper type of absorption glass for an optical pyrometer: P. D. FOOTE.

Some characteristics of glasses in the annealing range: A. Q. TOOL and J. VALASEK.

Expansion coefficients of optical glasses: C. G. PETERS.

AFTERNOON SESSION, 2 P.M.

Symposium on Applied Optics, with Special Reference to the Future of the Optical Industry in this Country.

I. The optical industry in war time: DR. F. E. WRIGHT.

II. The readjustments of the industry to peacetime demands for, and the future of manufacturing in:

1. Optical glasses: DR. G. W. MOREY.

2. Photographic lenses and cameras: MR. C. W. FREDERICK.

3. Projection apparatus: DR. H. P. GAGE. 4. Microscopes, field glasses and telescopes: DR. H. KELLNER.

5. Photographic goods: DR. C. E. K. MEES. 6. Special research apparatus: MR. P. V. WELLS.

7. Spectacle lenses and optometry: MR. E. D.

TILLYER.

8. Illuminating engineering: DR. E. P. HYDE. III. The future of applied optics and the future needs for:

1. Education and training: DR. MEES and PROFESSOR SOUTHALL.

2. Scientific control_in_manufacturing: DR. KELLNER and MR. KEUFFEL.

3. Testing and research: DR. NUTTING.

EVENING SESSION, 7:30 P.M.

Business meeting.

The meeting was an enthusiastic one attended by about 80 persons. Resolutions were passed and committees appointed looking toward the closer cooperation between designers, manufacturers and users of optical goods of all kinds in America. The officers of the society for 1919 are: President Dr. F. E. Wright, Geophysical Laboratory, Washington.

Vice-president-Professor F. K. Richtymer, professor of physics, Cornell.

Secretary-Dr. P. G. Nutting, Westinghouse Research Laboratories.

Treasurer-Mr. Adolph Lomb, Bausch & Lomb Optical Company.

Members at Large of the Council-Professor J. P. C. Southall, Columbia University; Dr. L. T. Troland, Harvard University; Dr. W. B. Lancaster, Boston; Dr. H. E. Ives, Washington.

The next general meeting of the society will be held in connection with American Association for the Advancement of Science next December. P. G. NUTTING, Secretary

FRIDAY, JANUARY 17, 1919

CONTENTS

The American Association for the Advancement of Science :

Scientific Personnel Work in the Army: PROFESSOR E. L. THORNDIKE

Pumpelly's Reminiscences: PROFESSOR W. M. DAVIS

Professor Williams at Yale: PROFESSOR HERBERT E. GREGORY

Scientific Events:

An Institute of Physical and Chemical Research for Japan; The Depleted Herds of England, France and Italy; The Use of Nitrate during the War

Scientific Notes and News

University and Educational News

Discussion and Correspondence:

The Lille Society of the Sciences: Dr. CHARLES D. WALCOTTT. Root Pressure and Root Exudation: PROFESSOR ERNEST SHAW REYNOLDS. Generic Limitations: PROFESSOR O. A. STEVENS. Fireflies flashing in Unison: P. T. BARNES. Attempted Queen-bee Mating in a Double Tent Inclosure: L. V. FRANCE

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SCIENTIFIC PERSONNEL WORK IN THE ARMY1

THE sciences dealing with human nature were brought to bear upon the problems forced upon America by the world war. Anthropology and psychology, economics and statistics, history, sociology and education, were put in service to improve our use of manpower, just as the physical and biological sciences were put in service to increase, economize and mobilize the nation's physical re

sources.

Consider a few illustrations. At one of the cantonments, within a few months' time, over 30,000 men were given a uniform standard intelligence-test and, as a dircet result of it, 600 men who would have been a detriment and even a positive danger to their fellow soldiers were sent away before time and money were wasted on their military education.

Certain very important institutions were receiving candidates a large percentage of whom were discarded, with little but discouragement and envy to show in return for the expense of their time and the government's money. Yet these candidates were chosen by a system which already represented the acme of comsense administered by extremely able men. A scientific study of some five hundred cases showed where much of the trouble lay and provided a remedy.

mon

Under the pressure of the war the regular army scheme for measuring the qualifications and efficiency of its officers could not be operated. Nor would it have been suitable for the two hundred thousand officers taken from civil life with only a few months of military training. A workable record and rating plan was prepared by an expert in applied psychol

1 Address of the vice-president and chairman of Section H, Anthropology and Psychology, Baltimore, December, 1918.