Annals of the New York Academy of Sciences

THE NEW YORK ACADEMY OF SCIENCES

(LYCEUM OF NATURAL HISTORY, 1817-1876)

OFFICERS, 1915

President-GEORGE FREDERICK KUNZ, 601 West 110th Street
Vice-Presidents-CHARLES P. BERKEY, RAYMOND C. OSBURN,
CHARLES BASKERVILLE, CLARK WISSLER

Corresponding Secretary-HENRY E. CRAMPTON, American Museum
Recording Secretary-EDMUND OTIS HOVEY. American Museum
Treasurer-HENRY J. COCHRAN, 389 Fifth Avenue
Librarian-RALPH W. TOWER, American Museum
Editor-EDMUND OTIS HOVEY, American Museum

SECTION OF GEOLOGY AND MINERALOGY

Chairman-CHARLES P. BERKEY, Columbia University
Secretary-A. B. PACINI, 2704 Bedford Ave., Brooklyn

SECTION OF BIOLOGY

Chairman-RAYMOND C. OSBURN, 557 West 124th Street
Secretary-WILLIAM K. GREGORY, American Museum

SECTION OF ASTRONOMY, PHYSICS AND CHEMISTRY

Chairman—CHARLES BASKERVILLE, College of the City of New York Secretary ERNEST E. SMITH, 50 East 1st Street

SECTION OF ANTHROPOLOGY AND PSYCHOLOGY

Chairman-CLARK WISSLER, American Museum
Secretary-ROBERT H. LOWIE, American Museum

The sessions of the Academy are held on Monday evenings at 8:15 o'clock from October to May, inclusive, at the American Museum of Natural History, 77th Street and Central Park, West.

Dates of publication and editions of the brochures..

List of illustrations......

iii

iv

Geological Reconnoissance of Porto Rico. By CHARLES P. BERKEY.

(Plates I-III).................

1

List of Greater Antillean Spiders, with Notes on Their Distribution.

By FRANK E. LUTZ.....

71

Volcanic Dust Veils and Climatic Variations. By HENRYK ARCTOWSKI... 149

Statistical Study of Variation in Spirifer mucronatus. By CHARLES C.

Review of the Pleistocene of Europe, Asia and Northern Africa. By

HENRY FAIRFIELD OSBORN.......

215

Present Status of the Problem of the Origin of the Tetrapoda. By WIL-

LIAM K. GREGORY. (Plate IV).......

317

Biochemical Studies of Selenium. By VICTOR E. LEVINE. (Plate V).

Records of Meetings, 1915. By HENRY E. CRAMPTON..

Membership Lists, 31 December, 1915.

385

395

463

LIST OF ILLUSTRATIONS

Plates

I.-Relief Map of Porto Rico.

II.-Geological Reconnoissance Map of Porto Rico.

III.-Generalized Geological Cross-sections of the Island of Porto Rico.
IV. Right Pectoral Girdle and Limb of Sauripterus taylori Hall.
V.-Illustrations of Biological Reductions of Selenium Compounds.

Text Figures

Page

Diorite porphyry sills.....

Relief features characteristic of the interior ranges of Porto Rico..

Partially destroyed dune sand deposits of the San Juan formation..

Unconformity below the Arecibo formation..

Typical shale occurrence.....

Interbedded coamo limestone layers with massive tuffs.

Photomicrograph of a typical thoroughly indurated andesitic ash.

Photomicrograph of a typical weathered shale from Fajardo Playa.

Photomicrograph of a foraminiferal shale from the Bayamon-Comerio

road ...