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From Saunders

ROMER-A Shorter Version of

The Second Edition ofThe Vertebrate Body

Dr. Romer has condensed his outstanding text so that it may beused effectively for short courses in comparative anatomy. This isnot merely an abridgement achieved by cutting out entire sections-but a condensation by careful rewriting. The major items of theoriginal work are incorporated and the details of lesser importanceare omitted. Clarity and understanding are not sacrificed. All ofthe 390 excellent illustrations in the longer book are retained inthis book. The first three chapters including introductory andnatural history topics and the handy appendices are reproducedwithout change. Anatomy of the vertebrates is treated in a trulycomparative manner, without overemphasizing the human struc-ture. Embryology is presented to establish an understanding ofhomology and to remind the student of the importance of thetime element in the stages of development.By ALFRED SHERWOOD ROMER, Alexander Agassiz Professor of Zoology, and Director, Museumof Comparative Zoology, Harvard University. 486 pages, 6W2' x 9¼/4", with 390 illustrations.

New-Just Ready.

- 2 New Books

CONTENTSIntroduction ----- _---- --------------------

The Vertebrate Pedigree-Who's Who Among the VertebratesCells and TissuesEarly Development of VertebratesThe Skin---_The Skeleton - --

The Skull ...Muscular System

Body Cavities -------------_-------------------Mouth, Pharnyx, Respiratory OrgansDigestive System _ -

Excretory and Reproductive SystemsCirculatory SystemSense Organs -,--The Nervous System ---

Appendices1. Synoptic Classification of Vertebrates2. Scientific Terminology - --

3. References ---

Index -.. 465

CARPENTER- Immunologyand

SerologyThis new book explains what is currently known about immunol-ogy and serology. It studies resistance to infectious disease andthe properties and behavior of antibodies formed within an animalin response to foreign antigenic substances. Help is given in theclassification of bacteria, plants and animals, and identificationof certain of their components. Controversial material is presentedso that the student can see that the field is young and what de-velopments lie ahead. The author covers the nature of infectiousdisease, normal protection, susceptibility, types of immunity,laboratory production of antiserums, chemical nature of anti-bodies, the role of lymphoid tissues and plasma cells in antibodyformation, response to antigenic stimuli and the Rh factor. Anti-gens are fully discussed-classes, detection, properties and activechemical groups.

By PHILIP L. CARPmETRm, Professor of Bacteriology, University of Rhode Island. 351 pages,618" x 91/4", illustrated. New-Just Ready.

CONTENTS

Infection and ImmunityThe Immune Reaction-Antigens _ _Serum Proteins -.....-- .Production of AntibodyThe Antigen-Antibody ReactionPrecipitation -

AgglutinationIsohemagglutination-Toxins and Antitoxins

112

24567496120141169186

Phagocytosis ---------------------------------.r----------------------- 210Cytolysis and Complement Fixation 229Antiviral Immunity -251Allergy --- 269

AppendixExperiments in Serology -299

Index 327

W. B. SAUNDERS COMPANY

West Washington Square Philadelphia 5

SCIENCE is published weekly by the AAAS, 1515 Massachusetts Ave., NW, Washington 5, D.C. Entered at the Lancaster, Pa., Post Office as second classmatter under the act of 3 March 1879. Annual subscriptions: $7.50; foreign postage, $1; Canadian postage, 50¢.

116

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6 JANUARY 1956 3

Purina tIMK Nutrition News

HOW MUCH ESTROGEN ARE

YOU FEEDING?

One of the big questions facinginvestigators today working withsmall animals is whether the dietthey are using contains harmfullevels of estrogenic activity.We can well understand your con-cern because there have been someunfortunate instances where labo-ratory animal feeds have been con-taminated with harmful levels ofestrogen.Actually, there are traces of estro-gen in milk, meat, clover and otherfoods but they are in such smallquantities that they are not harm-ful. Some of the more recentlyused feed ingredients, such asdiethyl-stilbestrol can be harmful,however.Purina has taken great pains inpreventing estrogen contamina-tion by means of several checks.

In the first place, there is no stil-bestrol or dinestral diacetate inthe plant where Laboratory Chowis manufactured.Secondly, Laboratory Chows arepacked in specially lined paperbags which prevent contamina-tion from other feeds in dealer'sstores that contain stilbestrol.Thirdly, as a final check on estro-genic activity, we run regularassays -on Laboratory Chows asthey are manufactured. The assaysare showing only normal estro-genic activity, less than normallyoccurs in fresh milk.You can rely on Purina's con-tinued watchfulness for harmfulestrogenic activity in our labora-tory animal diets because we areworking with large numbers ofsmall animals in our own labora-tories all the time.

RALSTON PURINA COMPANY, St. Louis 2, MissouriWith Over 5,000 Dealers, Coast to Coast, To Serve You

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SCIENCE, VOL. 123

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THE SCIENCE OF

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To equip your laboratory with theapparatus, equipment and chemi-

cals you need calls for a scientificsupermarket.

This scientifig supermarket is yourlaboratory supplier. Here you can findas many as twenty-five thousand itemsstocked, classified, and cataloged tomeet the needs of all laboratories. Here,too, are technically trained personnel,constantly working to improve appa-ratus and equipment.An important link in scientific sup-

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The manufacturers of scientific sup-plies, the laboratory supply houses, andtheir representatives have made a sci-ence of supply. This science has manytheories, but service to laboratories isa law.Your inquiries are always invited.

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apochromatic objectives, 1.40 N.A. achromaticsubstage condenser, and compensating eyepiecesprovide clear, detailed images of otherwisehard-to-see materials and structures. Find out howa B&L Research Microscope makes it easierfor you to do your best work.

SEE FOR YOURSELFIN LABORATORY DEMONSTRATIONWrite for demonstration and Catalog D-1010.Bausch & Lomb Optical Co.- 64201 St. Paul St.,Rochester 2, N. Y.

RESEARCH MICROSCOPES

8SCIENCE, VOL. 123

I

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SCIENCE, VOL. 1238

Kodak reports to laboratories on:how to bring somebody else's slide lecture back home ... riding the new speed vs

sharpness curve ... adding to an already imperfect list of reagents

Convention trophiesBumped into a lad the other daywho is director of photo services atone of the big Middle Western uni-versities. It was at a meeting of atechnical society, and he had spiedus in the act of outwitting a speakerwho was impressing the audience byzipping slide after slide of big, fattables of numerical data onto thescreen. There we sat in the darkwith a little camera, popping awayat each slide so that when we gothome we could take our own sweettime deciding just how impressedto be.We thought we would have a

chance to expound to the fellow alittle on film, aperture, and shutterspeed involved in this photographicfeat, but it turned out this type ofcagey operation is straight routinewith him and we couldn't tell him a

thing he didn't know already. Oneof the regular duties of his office isto supply staff members with cam-

eras to catch the slides at meetings.With any luck and a steady hand, a

camera no more elaborate than theKodak Pony 135, Model C, whichcomes with an f/3.5 lens for $33.75,should pick up readable copies of slideson Kodak Tri-X Film when shot wideopen at 1/25 sec. from a point in theroom where the screen image just fillsthe finder. It could provide somethintgmore definite to bring home from ameeting than a feeling of solidarity withone's discipline. (Caution: copying a

man's slides without his permissioncouild conceivably earn one a puliich inthe nose.)

Enlarging the breakthroughLooked back at now, the film emul-sion-making practices of, say 1953,seem unsophisticated. We shall haveto let the remark stand at that. Thefact is that there has been an abruptrise in a quasi-quantitative quan-tity, the product of film speed andsharpness.About measuring speed there is a

lot to be said, but we won't say ithere, except that the Kodak Tri-XFilm which we introduced a year or

so ago has significantly expandedthe scope of photography.

Sharpness, a subjective impres-sion, has now likewise had a metricimposed on it. There is a mathe-matical statement-termed acutance

-of the density variation across the

photographic image of a knife edge.It is quite different from resolvingpower, a quantity related to thesmallest repetitive detail distinguish-ably reproducible, whether the de-tail looks sharp or not.

Riding the new speed vs. sharp-ness curve, we here announce reac-tivation of the name Kodak Pana-tonmic-X Filnm to apply now to oursharpest roll film, 35mm and othersizes, for general photography. ItsExposure Indexes are 25 for daylightand 20 for tungsten. Its emulsion isless than half as thick as usual innegative film. This shortening of thepath along which light can scatteron its way down is part of the rea-son for the greater sharpness, butonly part. The thinness also speedsprocessing. As for resolving power,witness the following demonstra-tion, as filtered through the pressthat printed this page:

Kodak Panatonmic-X is an ex-treme, as is Kodiak Tri-X. For thosewho have been getting along justfine with the speed of Kodak Super-XX, but want the sharpness benefitof the 1954 breakthrough, we recom-mend a new 35mm and 70mm filmwe are calling by the old nameKodak Plus-X. The noble old nameSuper-XX is being retired, exceptfor sheet and aerial film.

Yet another reagent for CuThe world, it would appear, hasneed for yet another reagent forcopper, so now we give you Dicyclo-hexanone Oxalyldihydrazone (East-man 7175). The 14 Cu reagents al-ready listed in our catalog are notenough. Each has its own short-comings.

Diethyldithiocarbanmic Acid So-cliunm Salt (Eastman 2596) for ex-ample, forms interfering colors withiron, cobalt, nickel, and bismuthand calls for solicitude over mono-chromatism in applying Beer's Lawto measure the yellow complex itforms with copper. Diphenylthio-carbazone (Eastman 3092) demandsclose watch on pH to keep a rea-sonable specificity, besides beingconfusingly colored itself. 2,2'-Bi-quinoline (Eastman 6183) has theCu specificity, but with a molar ab-sorbancy index of only 5900, it is alittle low on sensitivity.Compare this figure with the

16,000 molar absorbancy index ofthe cupric complex of dicyclohexa-none oxalyldihydrazone, which oneScandinavian chemist first preparedby reacting oxalyl dihydrazidewith cyclohexanone and two otherScandinavian chemists put to workmeasuring copper in paper pulp.The sensitivity works out to about0.03 ppm. Of 48 other commonions tested, not one gave an inter-fering color. Lead, zinc, nickel, andparticularly cyanide did interfere,but forthrightly, by preventing ordelaying color formation, not bydissemblance.Beyond a doubt, even this nega-

tive interference will someday ex-asperate some analytical chemistinto devising yet another reagentfor copper. We hope to sell thatone, too.

Will you accept a gift, meanwhile, ofa procedural abstract for dicvclohexa-none oxalyldihydrazone in the determina-tion1 of copper in serum ? If you alsowant the chemical, we're afraid we haveto charge $2.50 for 5 grams of it asEastman 7175. Distillation Products In-dustries, Eastman Organic ChemicalsDepartment, Rochester 3, N. Y. (Di-vision of Eastman Kodak Company).

Already both of these new films areamong the most widely distributed manu-factured products in the United States.

This is one of a series of reports on the many productsand services with which the Eastman Kodak Company and

its divisions are ... serving laboratories everywhere6 JANUARY 1956

I

31

A Durable, Highly Sensitive, low-Cost Welch Balanceof Extreme Accuracy STAINLESS STEEL Construction

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