CONTENTS

PAGE

The Origin and Distribution of the Genera of the Fishes of

South America West of the Maracaibo, Orinoco, Amazon and

Titicaca Basins. By CARL H. EIGENMANN..

Growth in Trees. By D. T. MACDOUGAL.

I

7

The Action of Bases and Salts on Biocolloids and Cell-Masses.

By D. T. MACDOUGAL....

15

A Natural Group of Unusual Black Oaks. By WILLIAM TRE-

LEASE

31

The Fixed Glacial Anticyclone Compared to the Migrating Anti-

cyclone. By WILLIAM HERBERT HOBBS....

34

Discussion of a Kinetic Theory of Gravitation, and II, Some

New Experiments in Gravitation. By CHARLES F. BRUSH.. 43

Rose Atoll, American Samoa. By ALFRED GOLDSBOROUGH

MAYOR...

Tobit's Blindness and Sara's Hysteria. By PAUL HAUPT......

A New Hoplophoneus from the Titanotherium Beds. By WIL-

LIAM J. SINCLAIR...

The Control of the Foreign Relations of the United States: The

Relative Rights, Duties, and Responsibilities of the President,

of the Senate and the House, and of the Judiciary, in Theory

and in Practice. By QUINCY WRIGHT...

The "Turtle-Oreodon Layer" or "Red Layer," a Contribution

to the Stratigraphy of the White River Oligocene (Results of

the Princeton University 1920 Expedition to South Dakota).

By WILLIAM J. SINCLAIR..

...

Entelodonts from the Big Badlands of South Dakota in the Geo-

logical Museum of Princeton University. By WILLIAM J.

SINCLAIR

...

62

71

96

99

456

467

On Mean Relative and Absolute Parallaxes. By KEIVIN BURNS 496

The Nature and Origin of the Fishes of the Pacific Slope of

Ecuador, Peru and Chili. By CARL H. EIGENMANN... 503

Measurement of Star Diameters by the Interferometer Method.

By F. G. PEASE...

The Peopling of Asia. By ALES HRDLIČKA..

......

524

535

An Electro-Chemical Theory of Normal and Certain Pathological

Processes. By G. W. CRILE, M.D...

...

546

The Coudersport Ice Mine. By EDWIN SWIFT BALCH........ 553

Obituary Notices of Members Deceased:

Members who have not as yet sent their photographs to the Society will confer a favor by so doing; cabinet size preferred.

It is requested that all correspondence be addressed

TO THE SECRETARIES OF THE

AMERICAN PHILOSOPHICAL SOCIETY

104 SOUTH FIFTH STREET

PHILADELPHIA, U. S. A.