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Saunders books

Odumn-Fundamentals of EcologySince its publication, Odum's Fundamentals of Ecology has established itselfas the definite leader in its field as shown by enthusiastic reviews and widespreadadoption by teachers of ecology. Here are some typical reviews.

"Professor Odum's book has great attractions. It is not too long or ex-

pensive, cites plenty of recent research on live topics, successfully deals withpopulation ecology, and is written in a lively and even provocative style andillustrated with very carefully chosen examples."

JOURNAL OF ANIMAL ECOLOGY

"Dr. Odum . . . has successfully marshaled the rudiments of ecologicalknowledge into a well organized, readable basic text." ECOLOGY

"This book commends itself to evolutionists as a radical and refreshinglydynamic approach that emphasizes principles and concepts." EVOLUTION

By EUGENE P. ODUM, Ph.D., University of Georgia, Athens, Georgia. 384 pages, with 119 illustrations. $6.50.

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Walker-Vertebrate DisseetionThis practical lab-anual compares the systems of three levels of organisms bythoroughly studying the dogfish, mudpuppy, cat and rabbit. It helps the studentunderstand the major anatomical transformations that have occurred in thevertebrates in the course of their evolution.

Directions for dissection are precise. and helpfully illustrated with labeleddrawings. Summary paragraphs accompany the instructions and point outto the student how this particular species conforms or deviates from the generalgroup. The material does not replace the textbook but helpfully supplementsit. Appendices explain the preparation of specimens.

This manual will accompany any comparative anatomy text and is easilyadapted to the emphasis and length of your particular course.

By WAEN F. WALCER, JR., Ph.D., Asociate Professor of Zoology, Oberlin College, Ohio. 331 pages,illustrated. $3.50.

W. B. SAUNDERS COMPANY

West Washington Square Philadelphia 5SCIENCE is published weekly by the AAAS, 1515 Masachusetts Ave., NW, Washngton 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, 500.30 SEPTEMBER 1955 579

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NEW! B&L ACCESSORY SLOT COMPENSATORSPEEDS BIREFRINGENCE MEASUREMENTSThis important quality control and research aid quickly andefficiently measures phase difference; speeds determination ofoptical character or sign. Direct-reading magnified scale, cali-brated in millimicrons; no computation or conversion needed.Readings correct to ±2% over a range of 0 to 2700 millimi-crons. Fits all American microscopes of current design.

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582 SCIENCE, VOL. 122