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Educational Psychology

By DANIEL STARCH, Ph.D., Associate Professor of Psy-
chology and Education in the University of Wisconsin. Cloth,
Crown Octavo, 473 pages. Published June 24th.

"The aim of education is to change human beings for the better so that they will have more humane and useful wants, and be more able to satify them." In his new text-book, "Educational Psychology," Professor Starch uses th s definition by Thorndike as his point of departure. He considers the fundamental problems of educational psychology to be the determination of the capacities which human beings possess for acquiring the changes, and the investigation and evaluation of methods by which these changes may be brought about; accordingly, he recognizes two large divisions in the field of educational psychology; first, the native equipment of human beings; secondly, the psychology of learning. The book treats these two major subdivisions separately; the first includes considerations of the nature of human capacities, variation and inheritance of mental traits, and measurement of mental equipment, the second deals with the physiological and more strictly psychological aspects. An extensive third part considers in detail the problems and practices of schools, and gives special attention to each of the subjects commonly taught.

In Preparation

Vertebrate Zoology

By HORATIO H. NEWMAN, Ph.D., Associate Professor of
Zoology and Embryology, in the University of Chicago. Cloth,
Crown Octavo, about 545 pages, 220 illustrations.

Chapters:

TABLE OF CONTENTS

I- Principles of Vertebrate Morphology. II - The Phylum Chordata. III-The Origin and Evolution of the Vertebrates. IV-Cyclostomata. V-Pisces. VI - Amphibia. VII- Reptiles. VIII-Aves. IX-Mammalia.

This volume is intended for use as a text-book in college courses in vertebrate zoology and comparative anatomy. Professor Newman approaches his subject from the dynamic rather than the structural po nt of view; thus the physiological, phylogenetic, ecological, and evolutionary aspects of vertebrates are particularly emphasized; but careful attention is also given to anatomical facts and data.

The book is written in the light of the most recent advances in biology, making use of important new conceptions and experimental evidence bearing upon the evolution and comparative study of vertebrates.

THE MACMILLAN COMPANY

PUBLISHERS

NEW YORK

THE SEXUAL LIFE

MALCHO

T

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SCIENCE

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GROWTH IN ORGANISMS1

THE main proposals discussed in this address were as follows:

1. The development of an organism from the spore or embryonic stage includes the two processes of auxesis or enlargement and of differentiation both in the single cells or elements and in the organs.

2. The present studies are based upon the conception that living matter is composed mainly of pentosans and albumins or albumin derivatives with lipins as a minor component. The proportion of the main components may vary from nearly a hundred per cent. to nearly zero.

3. The principal and characteristic substances of the two groups are practically nondiffusible and hence come together only as an intimate mixture in a colloidal condition, with varying arrangement.

4. Growth of living matter consists of hydration with accompanying swelling and of accretion of solid matter, the two processes being actually independent.

5. The hydration of the substances belonging to the two main components is affected in an opposite manner by hydrogen ions, and is variously modified by temperature and other conditions: the rate and amount of growth is a resultant of several reactions.

6. Accretions of new material include the absorption of salts which tend to restrict hydration and the incorporation of amino-compounds. So-called nutrient salts do not constitute food but may act as catalysts or releasers of energy in other substances and as controls.

7. The enlargement of cells is almost entirely by the swelling which results from hy

1 Presidential address, Pacific Division of the American Association for the Advancement of Science meeting at Pasadena, June 19, 1919. Manuscript abbreviated by the author.

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