Fripay, SEPTEMBER 13, 1918 
CONTENTS 
John Duer Irving: Dr. JAMES F. Kemp ..... 255 
Race Appreciation in Latin America: PHILIP 
AINSWORTH MEANS ...0.0.. c0cccsne cue 256 
The American System of Agricultural Educa- 
tion and Research and its Réle in Helping to 
Win the War: Secretary Daviv F. Houston. 260 
Scientific Events :— 
Trench Fever and Lice; Granite for Building 
in 1917; The Proceedings of the National 
Academy of Sciences; Squaw Island ...... 262 
Scientific Notes and News ...........000s008 266 
University and Educational News ..........- 269 
Discussion and Correspondence :— 
Barley Bread, Optimum Reaction and Salt 
Effect: LorRAINE L. LANDENBERGER. Con- 
certed Behavior of Terrestrial Mollusks: T. 
C. STEPHENS. A Country without a Name: 
Proressor J. S. Moore, Dr. Inco W. D. 
ERANARIER ees wie Nia! once! > BINS diel ell Ole ielersis, brarstaiala 269 
Scientific Books :— 
Parker on City Milk Supply: PROFESSOR 
EG RONG Shs conteiescscavee eeeddies 272 
Special Articles :— : 
Corpeus Luteum and the Periodicity in the 
Sexual Cycle: Dr. Leo LOEB ............. 273 
The Ohio Academy of Science: PRoressor Ep- 
WAHD: Dip ien en Cimeueal et  aeieie Giusy ca 'o + =U oles 277 
MSS. intended for publication and books, etc., intended for 
review should be sent to The Editor of Science, Garrison-on- 
Hudeon, N. Y. 
JOHN DUER IRVING 
Just at the close of last July, not only 
personal friends, but geologists in general in 
America were shocked and grieved to learn of 
the death of Captain John Duer Irving of the 
11th U. S. Engineers, professor of economic 
geology in the Sheffield Scientific School of 
Yale University, on leave. Alike as active 
and productive geologist, as successful and de- 
voted teacher, and as managing editor of the 
magazine Economic Geology from its begin- 
ning in 1905, Professor Irving was known and 
esteemed by a very wide circle. He was born 
August 18, 1874, in Madison, Wis., where his 
father Roland Duer Irving was professor of 
geology in the State University, and was just 
starting his fruitful investigations in Lake 
Superior geology. John, the son, lived in 
Madison until his father’s all too early death 
in 1888. Mrs. Irving removed to the east and 
John was prepared for Columbia College, 
which he entered in 1892, representing the 
fourth generation of his family in the direct 
line, to be registered on the college rolls. He 
graduated in 1896 and took his doctor’s degree 
in 1899. 
Beginning in the vacation following his 
junior year, he had field experience each sum- 
mer, and worked successively in the Uinta 
Mountains of Utah; the Adirondacks in New 
York; the San Juan region of Colorado; and 
in the Black Hills of South Dakota. Partly 
from the example of his father and partly 
from the writer’s influence, economic geology 
became the branch which he specially followed. 
On taking his Ph.D. Dr. Irving joined the 
U. S. Geological Survey, and was assigned to 
a party in the Black Hills, and in time under 
the oversight of S. F. Emmons completed the 
professional paper on the ore deposits of the 
northern hills. His association led to his be- 
coming in later years Dr. Emmons’ closest 
associate in the revision of the famous Lead- 
