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REVISED 1948 EDITION

ANIMALSWITHOUT

BACKBONESAN INTRODUCTION TO THE INVERTEBRATES

By RALPH BUCHSBAUM

Completely up to date

S337 magnificent photographs-more than 150 of them new

Legeizds for photographs rewritten-and, as before, form an integralpart of the text

3 27 drawings and diagrams-many not included previouslyGravure illustrations numbered for easy reference

THE UNIVERSITY OF CHICAGO PRESS

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A proved and reliable text -Well over 200 collegesand universities are using the first edition in their classes."Not only contains adequate information effectively pre-sented and well selected but it is the only book on in-vertebrates whose illustrations do justice to the subject."-Carroll Lane Fenton, AMERICAN ASSOCIATIONFOR THE ADVANCEMENT OF SCIENCE. Hailed byscores of teachers: "A brilliantly successful textbook!""Fascinates the student without- the slightest sacrificeof scientific integrity . . ." "The superb illustrationsdo a great deal of the teaching . . ." v $5.00

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Biologist: M.S. Major training ecology, anatomy, general zoology.Seven years teaching and research experience. Desires summerposition. Box 293A, SCIENCE.

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Chemical Engineer: Seeks teaching position in electrochemistryand chemical engineering. Of Chinese birth. Years of experiencein research, plant management and teaching in United States.Ph.D. Columbia 1925. Box 300A, SCIENCE.Chemist: Woman, Sc.D. Sixteen years experience teaching.analytical, organic and biochemistry. Present salary $4500. Box296A, SCIENCE.

Experienced spectroscopist-physicist: Ph.D., seeks appointmentsouthern university and opportunity to develop a laboratory ofspectroscopy. Box 292A, SCIENCE.

Physiologist: Twenty-two years experience (physiology, anatomy,genetics, zoology). Publications. Box 298A, SCIENCE.

'Protein Chemist, specializing in physical-chemical techniques (elec-itrophoresis, diffusion, ultra-centrifugation, etc.) and experiencedin protein fractionation and isolation methods, is available astresearch consultant. Has well-equipped laboratory. Box 279A,SCIENCE.

Virologist: Ph.D. Research experience in virology, immunology,and chemotherapy. Publications. Administrative experience. De-sires change. Box 302A, SCIENCE.

Zoologist-Ecologist desires university or college teaching position.Candidate for Ph.D. in August, seeks place for fall semester, 1948.Major research interest invertebrate ecology, minors in plantecology, meteorology. Box 264A, SCIENCE.

Zoologist: Ph.D. desires college teaching position. Maior train-ing: vertebrate zoology, anatomy, nature study. Teaching ex-perience. Box 308A, SCIENCE.

16

Personnel PlacementASSISTANTSHIPS WANTED

Wanted: Zoology graduate assistantship, fall '48. B.S. degree,Oklahoma Baptist University. Wayne Martin, 0. B. U., Shawnee,Oklahoma.

POSITIONS OPENAssistant Control Bacteriologist for supervision of several tech-nicians in routine testing. Knowledge of pharmaceuticals de-sirable. Located in well-established mid-west pharmaceutical com-pany near large city. Box 289A, SCIENCE.

Wanted: Bacteriologist to take charge of laboratory. The workwill consist of evaluating new chemotherapeutic agents for theiractivity in vitro and in vivo. Midwest. Box 290A, SCIENCE.

Biologist: Masters or Ph.D. capable of developing courses inphysiology and bacteriology. Within limits other duties will de-pend on training and experience of applicant. Salary $2500-$3200.Apply to Dr. A. R. Keppel, President, Catawba College, Salisbury,N. C.

Cytologist: Ph.D. or M.D. opportunity to collaborate on long-term cytochemical and histochemical research developing and ap-plying new technics. University medical center. Box 277A,SCIENCE.

Wanted: An assistant professor in pharmacology, north centralarea, salary $4500-$5000 dependent upon training and ability.Position open 1 September 1948 or earlier. Excellent opportunityfor research. Box 304A, SCIENCE.

Physicists: Applications are invited for assistant and associate pro-fessorships in the department of physics, University of British Co-lumbia, Vancouver, B. C., Canada. Initial salary $3000 to $4100,depending upon qualifications. Duties will commence in September1948. These positions are open to young men who have not hadteaching experience. Enquiries should be addressed to G. M.Shrum, Head, Department of Physics.

Plant Pathologist: To develop program of basic and applied fungi-cide research in state experiment station. Excellent living andworking conditions and opportunity for advancement. Rank andsalary contingent on training and experience. Box 303A,SCIENCE.

Positions Open: (a) Ph.D. in pharmacology or physiology for keyposition in research division of large pharmaceutical company;should be interested in pharmacological development of syntheticorganic medicinals; East. (b) Bacteriologist; Ph.D. or M.D. forposition of instructor or assistant professor in bacteriology; teach-ing and research experience required; university medical school;middle west. (c) Assistant professor, general zoology and com-parative anatomy; young men's college; middle west. (d) Ph.D.or equivalent in pharmacology or physiology to join staff of liter-ature research department; knowledge of foreign languages un-necessary; duties include writing literature reviews; east. (e)Botanist; middle western university; rank: instructor or assistantprofessor; $4000 for Ph.D.; will consider one with Master's degree.(f) Sanitary chemist, with working knowledge of chemistry ofwater and sewage; experience in water filtration plants and sani-tary engineering laboratories advantageous; chemist, Ph.D., withinterest in sanitary chemistry field eligible; health department ofmodern community, new research institution $4900-$5900; south-west. S5-1 Medical Bureau (Burneice Larson, Director), Palm-olive Building, Chicago 11.

Pharmacy Teacher: Doctorate or equivalent, qualified and capableof developing and heading department within Pharmacy College.Salary commensurate with education and experience; other open-ings in pharmaceutical biological subjects, advancement possible.Middlewestern university. Reply giving details. Box 305A,SCIENCE.

Position Open: Assistant professor of zoology in a state university:Young man with Ph.D. with major interest in experimentalmorphology. Would be required to give a course in experimentalembryology and assist in teaching comparative anatomy andembryology. Ample time for individual research. Excellent op-portunity for promotion for the right man. Box 306A, SCIENCE.

CHARGES FOR CLASSIFIED ADVERTISINGRegular setting 10¢ a word. Minimum charge $2.50 foreach insertion. A box number counts as 8 words of theadvertisement (e.g. 25 words plus box number equals 33words). Make checks payable to the AAAS. All inser-tions must be accompanied by correct remittance and sent10 days in advance of publication date to the AdvertisgDepartment, AAAS 1515 Massachusetts Avenue, N. W.,Washinc~on 5. D.E

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