SCIENCE NEW SERIES FOIA UUT1 95SUBSCRIPTION, $6.00 VoN 102, NO. 2641 FRIDAYAUGUST 10 1945 SINGLE COPIES, .15 no. 102 No,64 Ba C t e rIolo I O g y Blakiston Laboratory Tecinique Books 1 1~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ STITT-STRONG Diagnosis, Prevention & Treatment of Tropical Diseases-7th Edition 1945 By RICHARD P. STRONG, M.D., Sc.D., D.S.M., C.B., Colonel M.C.U.S.A. Consultant to Secretary of War; Director of Tropical Medicine, U. S. Army Medical School, etc. Written by the best known authorities on tropical diseases, this timely and very praeti- cal book has been again reprinted to supply the demand. Special attention is given to the study of public health problems relating to diseases of tropical origin that may become endemic in temperate climates. All laboratory procedures are indexed by diseases. "It is doultful whether any scientific paper of marked importance published the last twenty years has missed the eagle eye of Professor Strong and his colleagues." Medi- cal Journal of Australia. STITT, CLOUGH and CLOUGH Practical Bacteriology,. Haematology and Re-td Animal Parasitology-9th Edition 1945 By Rear Admiral E. R. STiTT, Former Surgeon General U.S.N., PAUL W. CLOUGH, M.D., and M. C. CLOUGH, M.D., Johns Hopkins Medical School. Probably.the most widely used single volume in the laboratory, this book presents in four sections-Bacteriology-Haematology-Animal Parasitology and Pathological Examinations of the Various Fluids and Organs of the Body. An Appendix of labora- tory procedures and an Index of Diseases is included. MARSHALL Laboratory Guide in Elementary Bacteriology By M. S. MARsHALL, PH.D., University of California. This book provides well integrated material for a first course in bacteriology designed to orient the student in the problems and their implications. LEE The Microtomist's Vade Mecum-10th Edition Edited by J. B. GATENBY, PH.D., Trinity College, Dublin, and T. S. PAINTER, PH.D., University of Texas. An outstanding work on histological technique. A section on botanical methods is now included in the volume. THE BLAKISTON COMPANY 1012 WALNUT STREET PHILADELPHIA 5t, PA. Pleasesend me the following books: ........... ...................................................................................................................................... ....... ............................................................................................................................................................................................................................................. Name .. Address ........ Sel. 8-10 Published weekly by the American Association for the Advancement of Science at Lancaster, Pa. Entered as second-class matter July 18, 1923 at the Post Office at Lancaster, Pa., under the Act of March 3, 1879. 398 Illus. 1827 Pages 2 Volumes $21.00 208 Illus. 961 Pages $7.00 0 244 Pages $1.75 0 Illus. 784 Pages $9.00 Order-
Transcript
SCIENCE
NEW SERIES FOIA UUT1 95SUBSCRIPTION, $6.00VoN 102, NO. 2641 FRIDAYAUGUST 10 1945 SINGLE COPIES, .15
By RICHARD P. STRONG, M.D., Sc.D., D.S.M., C.B., Colonel M.C.U.S.A. Consultant toSecretary of War; Director of Tropical Medicine, U. S. Army Medical School, etc.Written by the best known authorities on tropical diseases, this timely and very praeti-cal book has been again reprinted to supply the demand. Special attention is givento the study of public health problems relating to diseases of tropical origin that maybecome endemic in temperate climates. All laboratory procedures are indexed bydiseases."It is doultful whether any scientific paper of marked importance published the lasttwenty years has missed the eagle eye of Professor Strong and his colleagues." Medi-cal Journal of Australia.
STITT, CLOUGH and CLOUGHPractical Bacteriology,. Haematology and Re-tdAnimal Parasitology-9th Edition 1945
By Rear Admiral E. R. STiTT, Former Surgeon General U.S.N., PAUL W. CLOUGH, M.D.,and M. C. CLOUGH, M.D., Johns Hopkins Medical School.Probably.the most widely used single volume in the laboratory, this book presents infour sections-Bacteriology-Haematology-Animal Parasitology and PathologicalExaminations of the Various Fluids and Organs of the Body. An Appendix of labora-tory procedures and an Index of Diseases is included.
MARSHALLLaboratory Guide in Elementary Bacteriology
By M. S. MARsHALL, PH.D., University of California.This book provides well integrated material for a first course in bacteriology designedto orient the student in the problems and their implications.
LEEThe Microtomist's Vade Mecum-10th Edition
Edited by J. B. GATENBY, PH.D., Trinity College, Dublin, and T. S. PAINTER, PH.D.,University of Texas.An outstanding work on histological technique. A section on botanical methods is nowincluded in the volume.
THE BLAKISTON COMPANY1012 WALNUT STREET PHILADELPHIA 5t, PA.
Name .. Address ........ Sel. 8-10Published weekly by the American Association for the Advancement of Science at Lancaster, Pa.
Entered as second-class matter July 18, 1923 at the Post Office at Lancaster, Pa., under the Act of March 3, 1879.
398 Illus.1827 Pages2 Volumes
$21.00
208 Illus.961 Pages
$7.00
0
244 Pages$1.75
0
Illus.784 Pages
$9.00
Order-
Karl Friedrich Mohr was born atCoblenz, November 4, 1806. He wasawarded his doctorate "summa cumlaude" from Heidelberg in 1832.
Mohr may, with justice, be calledthe father of the volumetric system ofanalyses. He was adept in devisingnew methods of volumetric analysisand new pieces of apparatus. Hedesigned the Mohr burette, varioustypes of pipettes, the pinch clamp,the cork borer, the automatic burette,a rapid dialyzer, the specific gravitybalance, and many other devices usedin laboratories. He was recognizedas the leading scientific pharmacist ofGermany.Mohr died October 5, 1879 at Bonn.
This is the second of a series of briefbiographies of eminent chemists sponsoredby The Coleman & Bell Co., ManufacturingChemists, Norwood, Ohio, U. S. A.
men o/f 4clievementin the World of Chemistry
KARL FRIEDRICH MOHRNovember 4, 1806-October 5, 1879
Research Spectrometer
Readings can be made to 20 seconds. The objectives have a 30mm aperture and 250mm f.l. The telescope is pro-vided with rack and pinion focusing and lOX Gauss Eyepiece. A bilateral slit with stainless steel jaws 1Omm long,an adjustable comparison prism and decker are mounted on the collimator.This spectrometer is recommended for research work in educational and industrial laboratories. It is a high gradeinstrument that assures satisfactory results through convenient manipulation and accurate measurements insuredby the rigidity of its parts, the stability and convenience of adjustments, and quality of the optical parts. Thelarge circle is provided with two verniers and is mounted on accurate and substantial centers.
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2 SCIENCE-ADVERTISEMENTS VOL. 102, NO. 2641
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8 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2641
SCIENCEVOL. 102 FRIDAY, AUGUST 10, 1945 No. 2641
Embryological Aspects of Hybrid Vigor in Pines: Color Reaction of Vitamin A on Acid Earths: DR.PROFESSOR JOHN T. BUCHHOLZ.............................................. 135 GERDA GERNSHEIM MAYER and DR. HARRY SO-
BOTKA. Correction on "Chronic IntermittentObituqary: Anoxia . . . ": PROFESSOR WARD C. HALSTEAD.Nevin M. Fenneman: DR. RAYMOND WALTERS. 142 How Stentor Anchors Itself: PRoFEssSOR E. A.Recent Deaths.........................................ANDREWS. The Threat of Anti-vivisection:DR.
Scientific Events: A. V. WOLF. The Mather Collection of Portraits:The Professional Training of Chemists; The DR. T. S. PALMER. The Houssay Journal Fund:American Society of Mechanical Engineers; Let- DR. HERBERT M. EVANS, DR. WALTER B. CANNON,ters from Scientific Men Abroad; The Retirement DR. JOHN F. FULTON and DR. CARL J. WIGOERS . 157of Professor Guyer of the University of Wisconsin 143 Scientific Books:
Scientific Notes and News ..... ............... 145 Statistical Analysis: DR. C. I. BLISS. AntibioticSpecial Articles: Agents: DR. CHESTER S. KEEFER. Weeds: DR.
Concerted Antibiotic Effect of Penicillin, Methio- H. A. GLEASON. Books Received ....... ......... 161nine, Threonine and Methionine Sulfoxide upon Science News .10Brucella, Eberthella, Salmonella and Shigella. DR.GREGORY SHWARTZMAN. The Benzyl Ester ofPenicillin: DR. M. L. TAINTER and OTHERS. TheFunctional Pathology of Frostbite and the Preven- SCIENCE: A Weekly Journal, since 1900 the officialtion of Gangrene: DR. KURT LANGE, DR. LINN J. organ of the American Association for the AdvancementBOYD and DR. LEO LOEWE. Action Spectrum for of Science. Published by the American Association forthe Photoperiodic Control of Floral Initiation in the Advancement of Science every Friday at Lancaster,Biloxi Soybean: DR. M. W. PARKER, DR. S. B. Pennsylvania.HENDRICKS, DR. H. A. BORTHWICK and DR. N. J. Editors: JOSEPHINE OWEN CATTELL and JAQUESSCULLY. A New Polysaccharide from Black CATTELL.Spruce (Picea Mariana): DR. F. E. BRAUNS ............... 148 Policy Committee: MALCOLM H. SOULE, ROGER ADA.s
Scientific Apparatus and Laboratory Methods: and WALTER R. MILES.A Simple Water Manometer for Recording Intes- Advertising Manager: THEO. J. CHRISTENSEN.tinal Activity: DR. STEPHEN Kitop and DR. TED A.tinal Activity: D TECommunications relative to articles offered for publicationLOOMIS. Use of a Double-Nozzled Spray Appa- should be addressed to Editors of Science, 1215 Fifth Avenue,ratus for the Application of DDT or Oils: DR. New York 29, N. Y.DONALD F. STARR. Marking Anopheles Mosquitoes Communications relative to advertising should be addressedtoTEco. CHRISTES9J5N, Advertising Manager, Smithsonianwith Fluorescent Compounds: DR. JOHN W. ZUKEL 155 Institution Building, Washington 25, D. C.
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EMBRYOLOGICAL ASPECTS OF HYBRID VIGOR IN PINES'By Professor JOHN T. BUCHHOLZ
UNIVERSITY OF ILLINOIS
THE hybrids between some species of pine affordexcellent examples of hybrid vigor in the F, genera-tion of the cross. During recent years, demonstra-tions of this hybrid vigor in pines have been madein the nursery of the Institute of Forest Genetics at
Placerville, California. The hybrids concerned are
not the result of crosses between inbred strains of a
species but are the hybrids between species and be-
tween varieties. Hybrid vigor has been observed in
F, plants from the crosses: Pinus monticola x P.
strobus; P. Jeffreyi x (P. Jeffreyi x P. Coulteri) thelatter a natural hybrid; P. Murryana x P. Banksiana;
1 Contribution in lieu of his address as Vice-presidentand Chairman of Section G (Botanical Sciences) for 1942,American Association for the Advancement of Science.
between certain geographic varieties or races of P.ponderosa and in other combinations. In seedlingstages, some hybrids have exceeded the growth of theparent species by an amount that appears to be muchgreater than that of maize. Righter2 has given a fewperformance records over a 3-4 year period of some
of these hybrids, which have greatly exceeded thewind-pollinated parents.
The possible manifestation of hybrid vigor duringdevelopment of the embryo became a subject of spe-cial interest to the writer, while he was visiting in-vestigator at the Institute of Forest Genetics, forseveral months during the summers of 1942 and 1944.
2 F. I. Righter, Jour. Forestry, 43: 131-137, 1945.
