SCIENCE—ADVERTISEMENTS 
Marine Biological Laboratory 
Woods Hole, Mass. 
Facilities for reseach in Zoology, 
Embryology, Physiology and Bot- 
any. Seventy-six private labora- 
tories, $100 each for not over three 
months. Thirty tables are avail- 
able for beginnersin research who 
desire to work under the direction 
of members of the staff. The fee 
for such a table is $50.00. 
INVESTIGATION 
Entire Year 
Courses of laboratory instruction 
with lectures are offeredin Inverte- 
brate Zooiogy, Embryology, Physi- 
ology and Mor bgloey and Taxo- 
nomy of the Algae. Each course 
requires the full time of thestudent. 
Fee, $50. Alecture course on the 
Philosophical Aspects of Biology 
and Allied Sciences is also offered. 
INSTRUCTION 
July 3 to August 13, 
1918 
Animals and plants, preserved, liv- 
ing, andinembryonic stages. Pre- 
served material of all types of 
2nimals and of Algae, Fungi, Liver- 
worts and Mosses furnished for 
classwork, or for the museum. Liv- 
ing material furnished in season 
as ordered. Price lists of Zoological 
and Botanical materia] sent on ap- 
pucation: ‘State which is desired. 
or price lists and all information 
regarding material, address 
GEO. M. GRAY, Curator, Woods Hole, Mass. 
The annua]announcement wil! be sent on application to The 
Director, Marine Biological Laboratory, Woods Hole, Mass. 
The Theory 
of the 
Relativity of Motion 
By RICHARD CHACE TOLMAN 
Professor of Chemistry, University of Illinois 
SUPPLY — 
DEPARTMENT 
Open the Entire Year 
This book presents an introduction to the Theory 
of the Relativity of Motion, a theory'which in the 
decade since the publicat?on of Hinstein’s first 
paper has become a necessary part of the theoret- 
ical equipment of every physicist. The method of 
treatment adopted is to a considerable extent orig- 
inal and part of the material itself appears here for 
the first time. Professor Tolman aims not only to 
introduce the study of the relativity theory to 
those previously unfamiliar with it but also to pro- 
vide the necessary methodological equipment for 
those who wish to pursue the theory in its more 
complicated applications. 
225 pages: paper, $1.50, cloth, $1.75 
Carriage extra 
The University of California Press 
Berkeley, California 280 Madison Ave., New York 
Published June 8 
CIVIC BIOLOGY 
By 
Clifton F. Hodge, The University of Ore- 
gon, and Jean Dawson, Board of 
Health, Cleveland 
As its title indicates, the purpose of 
this book is to present a thorough expla- 
nation of all the biological forces, both 
helpful and injurious, that profoundly 
affect community life and to show how, 
by united effort, the undesirable elements 
can be discouraged or exterminated, and 
how the beneficial can be fostered and 
preserved. j 
881 pages, fully illustrated, $1.50 
Ginn and Company 
New York Chicago London 
Dallas Celumbus San Francisco 
Boston 
Atlanta 
Publications of 
Carnegie Institution of Washington 
The publications of the Institution now number over 350 
volumes, the subjects including Anatomy, Archmology, Astron- 
omy, Botany, Chemistry, Economics and Sociology, Embry- 
ology, Experimental Evolution and Heredity, Engineering, 
Folk-Lore, Geology, History, International Law, Literature, 
Mathematics, Medicine, Nutrition, Philo.ogy, Physics, Zool- 
ogy. Classified and descriptive lists will be sent postpaid 
on appication. 
Recently Issued 
227. Contributions to Embryology, Nos. 20, 21, 22, and 23. 
Quarto, $4.00. This book contains the following papers 
not sold separately : y i 
Streeter, Groree L. The Histogenesis and Growth 
of the Otic Capsule and its Contained Periotic Tissue- 
spaces in the Human Embryo. 50 pages, 4 text 
figures and four plates. 2 
Van DER Srricut, O. The Genesis and Structure of 
the Membrana Tectoria and the Crista Spiralis of the 
Cochlea. 32 pages, 4 pipes: : e 
WHEELDR, THEODORA. Study of a Human Spina Bifida 
Monster with Encephaloceles and Other Abnor- 
malities. 23 pages, 4 plates. 
Ineatts, N. W. Human Embryo before the Appear- 
ance of the Myotome. 24 pages, 5 text figures, 4 
plates. 
In Press 
Contributions to Embryology, Nos. 24, 25 and 26. 
Quarto. This book contains the following papers not 
sold separately : 
Srreerer, Grorap L. The Developmental Alterations 
in the Vascular System of the Brain of the Human 
Embryo. 5 plates, 12 figures. _ j 
Cowpry, E. V. The Mitochondrial Constituents of 
Protoplasm. 120 pages, 2 plates, 3 figures. i 
Kunrromo, Kanan. The Development and Reduction 
of the Tail and the Caudal End of the Spinal Cord. 
36 pages, 4 plates, 2 text figures. 
All communications should be addressed to 
CARNEGIE INSTITUTION OF WASHINGTON 
WASHINGTON, D. C. 
271. 
