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APRIL 17, 1936 SCIENCE-ADVERTISEMENTS 3

4 SCIENCE-ADVERTISEMENTS VOL. 83, No. 2155~~~~~~~~~~~~~~~

McGrawtHill Presents

NEW BOOKSTextbook of Botany

By JOHN B. HILL, LEE 0. OVERHOLTS and HENRYW. Popp, Pennsylvania State College. McGraw-Hill Publications in the Agricultural and BotanicalSciences. 625 pages, $4.00

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Biological Effects of RadiationMechanisms and Measurement of Radiation, Appli-cations in Biology, Photochemical Reactions, Effectsof Radiant Energy on Organisms and OrganicProductsEdited by BENJAMIN M. DUGGAR., University ofWisconsin. Prepared by staff of specialists underthe auspices of the Committee on Radiation, Divi-sion of Biology and Agriculture, National ResearchCouncil. Two volumes (not sold separately), 1342pages. Special introductory price, $10.00. Priceafter publication, $12.00

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The first volume in the McGraw-Hill Series in Geography.The chief merit of the treatment lies in the ehoice ofmaterial, in the structure of its organization, and in themanner of its presentation. The three opening chaptersprovide a degree of orientation in the field of geography,together with certain basic facts and geographical tools.Then follow discussions of elements of earth, elementsof material culture, and the geographic realms. Theillustrations are a noteworthy feature.

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The new second edition of this successful text offers theonly complete presentation to date of the new theoriesof 'the ionization of acids and bases and of the mechan-ism of hydrolysis which have developed during the pastdecade. Other recent developments included are activitycoefficients, the new theories of inorganic colloidal solu-tions, and recent advances in the theory of reactionmechanisms.

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SCIENCE-ADVERTISEMENTS VOL. 83, NO. 21554

VoL. 83, No. 2155

A reception in the corridors of the Eastman School ofMusic is to follow the lecture. On Thursday eveningthe address is by Dr. Carl Snyder, for many yearsstatistician of the Federal Reserve Bank of New Yorkand formerly president of the American StatisticalAssociation, on the subject, "The Role of Capitalismin Civilization."On Friday morning members will proceed by train

or auto to Ithaca to join in celebrating the semi-centennial of Sigma Xi. All those in attendance atthe Rochester meeting have been invited by Sigma Xito participate in the Ithaca program, which will in-clude addresses on Friday afternoon and Saturdaymorning as well as a complimentary dinner given todelegates and visitors by the Cornell Chapter on Fri-day evening. This will be followed by the semi-cen-tennial address on "Scientific Research and SocialProgress."The hotel headquarters of the association will be

at the Seneca. All hotels will cooperate with theassociation for the meeting. Members desiring ac-commodations will communicate directly with thehotels. The following rates will apply:Seneca: Single, $3-$4.50; double, $3.50-$6; twin-beds,

$4-$7. Rooms with running water: Single, $2.50; double,$3.50-$4.Powers: Single, $2-$4; double, $3-$6; twin-beds, $6-

$7. Rooms with running water: Single, $2; double, $3.Rochester: Single, $2.50-$4; double, $4-$6; twin-beds,

$5-$6.Sagamore: Single, $3.50-$5; double, $5; twin-beds,

$6-$7.Hayward (especially desirable for parties coming

"stag"): Single, $2-$3.50; double, $3.50-$6.

In addition to the hotel rooms listed above, therewill be available a hundred rooms in the universitydormitories on the River Campus for June 16, 17 and18. These will be reserved for men only at $1.00 perday as long as the supply lasts. Requests for reserva-tions for these dormitory rooms may be made to theGeneral Superintendent of Buildings and Grounds,University of Rochester. To insure accommodationsbeing held in the dormitories, a check for $3.00 (forthree nights' occupancy) should accompany the reser-vation. This will be returned if notice to cancel isreceived on or before June 12.

Transportation from the city hotels to the campussis direct and will be easily effected. Railroad rates to

Rochester can not be announced as yet, but some pro-vision will be made and published notice given later.The regular preliminary announcement of the meet-ings with details will appear in SCIENCE early in May.

RECENT DEATHS AND MEMORIALSDR. ARTHUR BALDWIN DUEL, of New York City,

aural surgeon, chairman of the Board of Surgeons andvice-president of the Manhattan Eye, Ear and ThroatHospital, died on April 11 at the age of sixty-fiveyears.

DR. JOHN URI LLOYD, of the Lloyd Brothers Phar-maceutical Company of Cincinnati, formerly presi-dent of the Cincinnati College of Pharmacy, died onApril 9. He was eighty-six years old.

F. S. WILKINS, research assistant professor ofagronomy at Iowa State College, died on March 31at the age of forty-fsix years. Since his appointmentto the staff at Iowa State College in 1915 he had beenin charge of forage crops investigations. The resultsof his research have been published in a number ofexperiment station bulletins and journal articles.

DR. ROBnnT BiRiNY, specialist in diseases of the earand throat, Nobel laureate in medicine in 1914, diedin Upsala, on April 8, at the age of sixty years.

MAURICE THEfODORE HAMY, since 1898 astronomerat the Paris Observatory, a member of the ParisAcademy of Science, died on April 10. He wasseventy-five years old.A mEmORIAL service has been held in the great choir

of the Washington Cathedral in honor of Dr. WilliamH. Wilmer, formerly head of the Wilmer Institute ofthe Johns Hopkins Hospital.A MEMORIAL meeting for Ivan Pavlov, the Russian

physiologist, was held in the State Office Building, St.Paul, on April 7, under the auspices of labor leaders,Wahlfrid Engdall, Carpenters Local Union No. 7,presiding. The speakers were: The Man: ProfessorRodney B. Harvey, plant physiology, UniversityFarm, Minnesota. The Biologist: Professor DwightE. Minnich, department of zoology, University of.Minnesota. The Psychologist: Dr. John G. Rockwell,state commissioner of education. The Physiologistand Russian Medicine: Dr. Elias P. Lyon, dean ofthe Medical School, University of Minnesota. Biologyand Economics: E. H. H. Holman.

SCIENTIFIC NOTES AND NEWSDR. RUDOLPH MATAS, honorary chief of the surgical Havana, at the recent annual meeting of the South-

service at Touro Infirmary, was presented with a eastern Surgical Congress in New Orleans. The

decoration and the title of commander of the National presentation was made by Dr. Charles Edward J.

Cuban Order of Carlos Finlay and a diploma ,of Finlay, Havana, Cuba, son of Dr. Carlos Finlay.

honorary fellowship in the Academy of Medicine'.of AT the meeting of the Society of Experimental Psy-

SCIENCE366

VOL. 83, No. 2155

that are difficult to demonstrate by the conventionaldissecting methods. Representatives from three phylawere used: (1) a mollusk, Loligo pealei; (2) twoarthropods, Libinia emarginata and Limulus poly-phemus; and (3) an echinoderm, Asterias forbesi.After killing the animal, it was placed in a 30 percent. solution of nitric acid.For the arthropods an immersion of 24 hour,s was

sufficient to remove the inorganic salts of the exoskele-ton completely and macerate the underlying tissues-except the nervous tissue. The animal was removedfrom the acid bath and placed in a dish containingwater. By cutting with a fine pair of scissors alongthe lateral, anterior and posterior margins of thecarapace, this much softened structure was easilyremoved. The underlying tissues were then removedto expose the entire ventral nervous system. A finecamel's hair brush was found to be very useful inremoving bits of tissue lying around the ganglia andnerve fibers extending into the appendages. Placingthe dish containing the specimen under a gentle streamof water was effective in removing the remainingdebris and washing out the acid.With Loligo and Asterias a period of 12 hours in

the macerating fluid was sufficient to soften the tissuesadequately. With Asterias one needed only to pickaway the tube feet and surrounding tissues with apair of forceps in order to demonstrate the superficialnervous system. The method is a simple and efficientway of making class demonstrations. Moreover, apermanent preparation may be made by mounting theexposed systems in a suitable glycerine-jelly mass.

Cornwell2 has suggested the presence of the myelinsheath, with its fatty properties, in the vertebrates asthe explanation for the resistance to maceration, asshown by the central and peripheral nervous systems.The disappearance of a greater share of the sympa-thetic system he attributes to the fact that it is notentirely myelinated. This reasoning can not be usedto account for the effects upon the invertebrates, forit is generally agreed that in the invertebrates andeven in the cyclostomes a myelin sheath is not typicallydeveloped and is only characteristic of the adults ofhigher vertebrates. However, in addition to thenucleated sheath known as the neurilemma investingthe nerve fibers of the invertebrates, there is presentafter treatment with osmic acid a deep staining layerbetween the outer sheath and the axis cylinder in some

forms, e.g., Palaemon. Although this does not neces-

sarily indicate the presence of fat, Friedliinder3 sug-gested that this sheath is similar to the myelin sheath

2 Ibid.3 B. Friedliinder, Mitth. zool. Sta. Neapel, Bd. 9, Heft

2, S. 205-265, 1889.

in the vertebrates. On the other hand, the electricalstimulation of molluscan nerve fibers reveals a break-down in conduction much more rapidly than whenusing the same stimulation on vertebrate nerve fibers.This perhaps indicates the absence of a myelin sheath.By applying acetone or 95 per cent. alcohol to iso-

lated nerve fibers of the forms we studied, we did notobserve a clear space between the axis cylinder andthe neurilemma which, if present, would indicatemyelination. Furthermore, when a 2 per cent. solu-tion of acetic acid, of which a few drops are placedat the edge of the cover slip and drawn through byfilter paper, the preparation does not show the per-sistence of fat droplets, although albumin granulesdisappear optically. In Loligo, Limulus and Libiniathe staining of isolated nerve fibers with Sudan IIIdid not reveal the presence of any region of fat-likesubstance between the neurilemma and axis cylinder.However, in Asterias the fibrils have a more or lesscentral position, with a rather densely staining regionsurrounding them. This region is composed of epi-thelial cells of mesodermal origin which may possiblyserve as a protective covering. Apparently, in theinvertebrates there must be some inherent property ofthe nervous tissue which re,sists the action of themaeerating fluid, since the fibers are generally withouta heavy protective sheath.We are continuing our investigations on a variety

of forms, along the following lines: a determinationof the time necessary for the maceration process; acytological study of the nervous elements of theserepresentatives, using some of the more recent tech-niques; a chemical determination of the nervous tissuecomponents.

UNIVERSITY OF WISCONSIN

UNIVERSITY OF MISSOURI

N. L. SCEMEICHEL

J. E. ENGLISH

BOOKS RECEIVEDBROwN, PERCY. American Martyrs to Science through

the Roentgen Rays. Pp. xv + 276. 55 figures. Thomas.$3.50.

Collected Reprints, 1935. Illustrated. Woods HoleOceanographie Institution.

HUBBELL, THEODORE H. A Monographic Revision of theGenus Ceuthophilus. (Orthoptera, Gryllacrididae, Rha-phidophorinae). Vol. II, No. 1 of Biological ScienceSeries. Pp. 551. 2 figures. 38 plates. University ofFlorida. $3.75.

LEMON, HARVEY B. Cosmic Rays Thus Far. Pp. xviii4-128. Illustrated. Norton. $2.00.

MACMILLAN, WILLIAm D. Theoretical Mechanics: Dy-namics of Rigid Bodies. Pp. xiii + 478. 82 figures.McGraw-Hill. $6.00.

RYLE, JOHN A. The Aims and Methods of Medical Sci-ence. Pp. 44. Cambridge University Press, Macmillan.$0.75.

378 SCIENCE

APRIL 17, 1936 SCIENCE-ADVERTISEMENTS

SCHOOLAND SOCIETY

EDITED BY J. McKEEN CATTELLCONTENTS

MARCH 21A Design for Scholarship: ISAIAH BOWMAN.The Few and the Many in Education: GEORGE E. VINCENT.Educational Events:

The British Government Education Bill and the Churchof England; Grants to Harvard University for Researchand Publication in the Humanities; The New CurricularProgram at the University of Pittsburgh; Report of theOregon High-School Contacts Committee; The FourthCongress on Business Education; School Executives Con-ference at Denver.

Educational Notes and News.Discussion:

WVhy not Try Education?: JOHN D. MCGANN.Special Correspondence:

Modern Trends in French Education: ADOLPHE J. DICK-MAN. Teaching College Freshmen to Make a Bibliogra-phy: A. BEATRICE YOUNG.

Quotations:The Heidelberg Invitation.

Educational Research and Statistics:The Status of Geology in Junior Colleges: EDWARD J.ZIELBAUER.

MARCH 28Educational Books of 1935: JOSEPH L. WHEELER.Educational Events:

Grants to Teachers of Languages in London; Gifts toNew York University; Education for Peace; FederalFunds for the Care of Children; The Milbank MemorialFund; The Discontinuance of Seth Low College atBrooklyn; Public Forums of the Federal Office of Edu-cation; The Walter Williams Memorial Campaign at theUniversity of Missouri; Appointments and Promotionsat Teachers College, Columbia University.

Educational Notes and News.Discussion:

The Present Situation in Regard to the Child LaborAmendment: GERTRUDE ROBINSON. De Germanis: ERNSTKOCH. A Prophecy Come True: MARY ROGERS MILLER.

Special Correspondence:The American Museum of Natural History as a Labora-tory School for Student Teachers: GRACE FISHER RAM-SEY. The Two-unit Plan at Mount Holyoke College:ROGER W. HOLMES.

Reports:Recommendations of the Presidents of Land Grant Col-leges for Negroes.

Educational Research and Statistics:The Ordinary Objective Test as a Possible Criterion ofCertain Personality Traits: LLEWELLYN N. WILEY andOTIS C. TRIMBLE.

APRIL 4Harvard, Present and Future: JAMES BRANT CONANT.Educational Events:

The Workers' University of Mexico; Awards of Ad-vanced Fellowships for Study in Belgium; Public SchoolLibrary Statistics; Cooperative Courses of the BostonMuseum of Fine Arts and Radcliffe College; ExpansionProgram at Nassau College, New York University; TheSummer Institute for Social Progress at Wellesley Col-lege; The Summer Session of Columbia University; Con-ference on Low-Cost Housing; A Memorial in Honor ofCharles De Garmo; The New President of Iowa StateCollege.

Educational Notes and News.Discussion:

The Plight of American Youth: M. B. SCHNAPPER.Higher I. Q. and Lower A. Q.: CHARLES W. PALMER.

Special Correspondence:Self-government in a Correctional School: SARAH E. D.STURGES.

Quotations:The Princeton Travesty on Bonus Hunters.

EDUCATIONAL REVIEWEdited by WILLIAM McANDREW

Comments on Things Educational:A Great Convention.

Monthly Survey of Educational Books:Social Studies; History Courses; Saint Just, Terrorist;The Lincoln Legend; More Zest for Life; Slow Learners;Educational Theory and Practice; Kindergarten; Workand Play with Words; Beloved Latin School; The 'TeenYears; Counselling; Examination and Grading in Uni-versities; Adult Education; English and Literature;Library; Science and Mathematics; Manners; Printing.

APRIL 11Some Possible Consequences of Advancing Standards in

Schools and Colleges: DR. JAMES R. ANGELL.-Educational Events:

School Medical Service in Great Britain; The WalterHines Page Traveling Scholarships; The Establishmentin New York City of a Bureau of Children's Adjust-ment; The "Teachers College News" of Columbia Uni-versity; Conferences of the Public Education Associa-tion; Testimonial Luncheon to Dr. Henry R. Linville.

Educational Notes and News.Discussion:

On the Frontier in Citizenship Education: C. E. HAGIE.Case Histories for All Pupils: W. W. LUDEMAN.

Special Correspondence:A Fifth Year for Secondary School Teachers at MountHolyoke College: STUART M. STOKE.

Quotations:Heidelberg, Spinoza and Academic Freedom; The LittleRed Rider.

Reports:John Simon Guggenheim Memorial Fellowships.

Societies and Meetings:The Portland Convention.

5

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THE SCIENCE PRESSGRAND CENTRAL TERMINAL, NEW YORK CITY

11