SCIENCE-ADVERTISEMENTS 11

d41 e~e4a" (G" e~e. I

]CHESTER]THE NATURE AND PREVENTION OF PLANT DISEASES

By K. STARR CHESTERDepartment of Botany and Plant PathologyOklahoma Agricultural Experiment Station

This modern text provides the material neededby students in an elementary course in plantpathology as part of the background for usefulwork in agriculture. For students majoring infield crops, horticulture, soils, entomology andrelated fields, this text is being used with suc-cess in introducing the essential features of thescience and providing the detailed and specificdirections needed on plant disease control.Lists of disease-resistant crop varieties, tradenames as well as compositions of fungicides,

207 Illustrations.

and working directions for putting theory intopractice are included.

Emphasis is given to the economic importanceof each disease and the crop in which it occurs. . .to environment as it conditions the devel-opment of contagious disease . . . and to theepiphytological peculiarities of plant diseases.

Chapters are sufficiently independent that theirorder can be modified to suit any particularneeds.

584 Pages. $4.50

Reviewers say:-

"Excellent discussions of methods, parasitism, etiology, epiphytology, quaran-tine and immunity.' '-Bios

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Pleasesendand charge to me, a copy of CHESTER 'S PLANT DISEASES...................................................... $4.50

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DECEMBER 7, 1945

2~~~~~~~~~~~~~~~~~.4 ,A -Selected List of

Byc~% AW % 3OUTLINES OF PHYSICALGEOLOGY

By CHESTER R. LONGWELL, Henry Barnard DavisProfessor of Geology, Chairman of the Depart-ment; ADOLPH KNOPp, Sterling Professor ofGeology, and Director of Graduate Studies; andRICHARD F. FLINT, Professor of Geology; allat Yale University

Second edition; 1941;381 pages; 6 by 9j; $2.75

OUTLINES OF HISTORICALGEOLOGY

By the late CHARLES SCHuCHERT and CARL 0.DUNBAR, Professor of Paleontology and Stratig-raphy, Director of Peabody Museum, Yale Uns-versity

Fourth edition; 1941;291 pages; 6 by 9*; $2.50

OUTLINES OF GEOLOGYBy CHESTER R. LONGWELL, ADOLPH KNOPP,RICHARD F. FLINT, the late CHARLES SCHUCERTand CARL 0. DUNBA&R

Second edition; 1941;672 pages; 6 by 9j; $4.00

TEXTBOOK OF GEOLOGYPart I-Physical Geology

By CHESTER R. LONGWELL, ADOLPH KNoPP andRICHARD F.:FLINT

Second edition; 1939;543 pates; 6 by 9*; $3.75

TEXTBOOK OF GEOLOGYPart 11-HHistorical Geology

By the late CHARLES SCHUCHERT and CAL 0.DUNBAR

Fourth edition; 1941;544 pages; 6 by 9j; $4.00

ROCKS AND ROCK-MINERALSBy the late Louis V. PIRSSON and ADOLPHKNOPF

Second edition; 1926;426 pages; 51 by 8*; $3.50

PRINCIPLES OF STRUCTURALGEOLOGY

By CHARLES M. NEVIN, Professor of Geology,Cornell University

Third edition; 1942;320 pages; 6 by 9*; $3.50

SdneeeDANA'S SYSTEM OFMINERALOGY

Rewritten and enlarged by CHARLES PALACHE,the late HARRY BERMAN, CLIPPORD FRONDEL; allat Harvard UniversityVolume I-Elements, Sulfides, Sulfosalts, Oxides.

Seventh edition; 1944;834 pages; 6 by 9*; $10.00

DANA'S MANUAL OFMINERALOGY

Revised by CORNELIUS S. HURLBUT, JR., A8s0so-ate Professor of Mineralogy, Harvard University

Fifteenth edition; 1941;480 pages; 6 by 9*; $4.00

INDEX FOSSILS OFN'ORTH AMERICA'

By HERVEY W. SHIMER, Professor Emeritus ofPaleontology, and ROBERT R. SHROCK,iAssooiateProfessor of Geology; both at MassachusettsImtitute of Technology

1944; 837 pages; 8 by 11; $20.00

EARTH SCIENCESBy J HARLEN BRETZ, Professor of Geology,University of Chicago

1940; 260 pages; 5j by 8j;College edition $1.75

ECONOMIC MINERAL DEPOSITSBy ALAN M. BATEMAN, Professor of EconomicGeology, Yale University

1942; 898 pages; 6 by 9*; $6.50

ERUPTIVE ROCKSBy S. JAMES SHAND, Professor of Geology,Columbia University

Second edition; 1943;444 pages; 5* by 8*; $5.00

X-RAY CRYSTALLOGRAPHYBy M. J. BUERGER, Associate Professor of Min-eralogy and Crystallography, Massachusetts In-stitute of Technology

1942; 531 pages; 6 by 9*; $6.50

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12 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2658

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SCIENCE-ADVERTISEMENTS

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14 SCIENCE-ADVERTISEMENTS VoL. 102, No. 2658~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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DECEMBER 7, 1945 SCIENCE-ADVERTISEMENTS 15

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SCIENCE-ADVERTISEMENTS 15DECEMKBER. 7, 1945

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SCIENCE-ADVERTISEMENTS

STAPHYLOCOCCUS AUREUS 60,000 Xas seen with the RCA Electron Microscope

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20 SCIENCE-ADVERTISEMENTS VoL. 102, No. 2658