L SENESCENCE By G. STANLEY HALL, Ph.D., LL.D. A complete presentation of the subject of Age, the last df of life, from a number of viewpoints. Price, $5.00. D. APPLETON AND COMPANY, New York SCIENCE AND HUMAN AFFAIRS y WINTERTON C. CURTIS, Professor of Zoology in the University of Missouri. A discussion of the relation of science and the scientific pirit to the problems of modern life and civilization. rice, $4.00. HARCOURT, BRACE & CO. West 47th Street, New York City MINERALOGY Better service in the supplying of Living and Preserved Material and Microscopic Slides. If you mark your order "RUSH," shipment will be made on the day following receipt of order. Our location enables us to specialize, both as to price and quality, on frogs, crayfish, clams, grasshoppers, pig embryos, etc. Injected Cats, Turtles, Frogs and Cryptos of really first class quality. Insect Life Histories. Osteological Preparations. Microscopes. Lantern Slides for Human Anatomy. WRITE FOR CATALOG PRICE LIST NO. 29 THE ANGLERS COMPANY 1534 West Lake Street, Chicago, Illinois Georgetown University SCHOOL OF MEDICINE AND DENTAL DEPARTMENT The Sixty-fourth Session began in September and continues eight and one-half months. Six-Year Collegiate and Medi.. cal Course leading to degrees B.S. and M.D. Practical laboratory work under special instructors, in Anatomy, Physiology, Chemistry, Histology, Pathology and Bacteriology. Ample facilities. for clinical experience and practical work in hospitals of city and in the University Hospital, containing in all over 3,000 beds. For particulars address GEORGE M. KOBER, M. D. STUDENTS' MICROSCOPES The "Praxis" Stand is the Student's model par excellence. Made throughout with the same ac curacy and finish as on Watson's highest priced Stands. A few special points are:- Standardization so that additional movements may be fitted as required. Lever fine adjustment. Constructed of two solid castings and indestructible. AL parts are slotted and sprung to compen sate for wear. Catalogue of Microscopes and accessories for W. WATSON & SONS, Ltd. 313, High Holborn, London, England Naturalists' Supplies We carry stock for prompt delivery I. Collecting Utensils. II. Breeding Apparatus and Cages for Living Animals. III. IV. V. VI. Cabinets, Insect Cases and Lining Material. VII. Explorers' and Collectors' Camp Outfits. VIII. IX. X. XI. XII. Oologists' Supplies. Aquaria. Books and Publications. Chemicals. K-S Museum Cabinets of Glass and Metal New Illustrated Biological Catalog will be sent free of charge upon application THE KNY-SCHEERER Department of Natural Science G. Lagai, Ph.D. CORPORATION 404-410 WEST 27TH STREET, NEW YORK CITY, N. Y. THE HISTORY OF THE CALORIE IN NUTRITION. Dr. Mildred R. Ziegler_-_-520 SOCIAL LIFE AMONG THE INSECTS. Professor William Morton Wheeler_____527 THE MARINE FISHERIES, THE STATE AND THE BIOLOGIST. Rewards for Working Inside the Atom; How the Chemist moves the World; The Cost of Niagara; Look out for Alpha Centauri; New Light on the Origin PUBLICATION OFFICE: 11 LIBERTY ST., UTICA, N. Y. New York Office: The Grand Central Terminal Single Number, 50 Cents. Yearly Subscription, $5.00 COPYRIGHT 1922 BY THE SCIENCE PRESS Entered as second-class matter November 9, 1921, at the Post Office at Utica, N. Y., under the Act of March 3, 1879. LIBRARY THE SCIENTIFIC MONTHLY DECEMBER, 1922 THE VEGETATION OF AUSTRALIA AND NEW ZEALAND THO By Professor D. H. CAMPBELL STANFORD UNIVERSITY HOSE parts of the world which for one reason or another are completely isolated show very plainly the effects of this isolation upon the animals and plants which inhabit them. The degree of specialization in these organisms is to a certain extent an index of the length of time the region has been shut off. A comparison of these organisms with those of other regions may throw light upon such problems as the changes in the distribution of land and water upon the earth's surface in the course of ages, and thus be of great interest to the geologist and geographer as well as to the biologist. If we compare the lands of the northern hemisphere, as they now exist, with the principal land masses of the southern hemisphere, we find the former to be very much more extensive than the latter. In the north there is a marked preponderance of land. in the polar and subpolar regions, which merge into the temperate regions in both the American and Eurasian continents. In the southern hemisphere there is an extensive almost absolutely barren polar continent, but the regions corresponding to the subarctic land masses of the north are entirely occupied by water; and the south temperate regions are completely separated from the antarctic continent by a wide stretch of sea. Moreover, the temperate regions of Australasia, South Africa and South America are widely separated from each other by the Atlantic, Pacific and Indian oceans. In extent the temperate regions of the south are much less than those of the northern hemisphere. As might be expected, this condition of things is accompanied by a much greater diversity in the temperate floras of the southern hemisphere than is the case in northern latitudes. This perhaps reaches its maximum in the Australasian region, the completely isolated Australian continent and the islands of New Zea Vol. XV.-31. |