The Twentieth Century Text Books of Biology.

PLANT RELATIONS, 12mo, cloth$1.10
PLANT STRUCTURES, 12mo, cloth1.20
PLANT STUDIES, 12mo, cloth1.20
PLANTS, 12mo, cloth1.80
ANALYTICAL KEY TO PLANTS, 12mo, flexible cloth.75

All by JOHN MERLE COULTER, A. M., Ph. D., Head of Dept. of Botany, University of Chicago.

They are already the preferred texts, and the reasons will be apparent on examination.

ANIMAL LIFE: A First Book of Zoology.

By DAVID S. JORDAN, M. S., M. D., Ph. D., LL. D., President of the Leland Stanford Junior University, and VERNON L. KELLOGG, M. S., Professor in Leland Stanford Junior University. 12mo. Cloth, $1.20. Now ready.

Not a book for learning the classification, anatomy, and nomenclature of animals, but to show how animals reached their present development, the effects of environment, their place in Nature, their relations to one another and to the human race. Designed for one-half year’s work in high schools. Send for sample pages.

ANIMAL FORMS: A Second Book of Zoology.

By DAVID S. JORDAN. M. S., M. D., Ph. D., LL. D., and HAROLD HEATH, Ph. D.,

Professor in Leland Stanford Junior University. Ready in February, 1901.

D. APPLETON AND COMPANY, Publishers, New York, Chicago, London.