REPORT OF NATIONAL MUSEUM, 1921. 85 
American petrologists, and took a deep interest in the development 
of this particular branch of the science. His large collections of 
volcanic rocks, made during his extensive trips throughout the prin- 
cipal volcanic districts of the world, were installed among the collec- 
tions of the Museum, where they remain accessible for reference and 
study, and form an important addition to the already large series 
of studied material in the department. 
During the early portion of his career, from 1880 to 1895, Doctor 
Iddings was connected with the United States Geological Survey, 
and was the author of several publications of importance by that 
organization. Among the most important may be mentioned : 
The Obsidian Cliffs of the Yellowstone National Park. 
On the Development of Crystallization in Igneous Rocks. 
On a Group of Volcanic Rocks from the Tewan Mountains. 
The Microscopic Petrography of the Eruptive Rocks of the Eu- 
reka District of Nevada. 
The Eruptive Rocks of Electric Peak and Sepulchre Mountains, 
and the chapters on petrography in part 2 of the monograph of 
the Yellowstone National Park. 
His best known personal publications are his translation of H. 
Rosenbusch’s Physiography of the Rockmaking Minerals (1898) ; 
Rock Minerals (1906) ; Igneous Rocks, 2 volumes (1909) ; and The 
Problem of Vulcanism (1914). He was also one of the most active 
and influential of the authors of the Quantitative Classification of 
Igneous Rocks (1903). A striking feature of his work was his 
accuracy and careful attention to detail. 
From 1895 to 1908 he was professor of petrology in the Univer- 
sity of Chicago, since which time he lived for the most part at Brink- 
low, Md., devoting himself largely to private work, and particularly 
to the petrology of the Pacific and South Sea Islands. 
He was a man of broad culture, dignified and gentlemanly bear- 
ing, and his loss will be everywhere most deeply felt. 
By the death of Mr. N. R. Wood, on November 8, 1920, the Na- 
tional Museum lost one of its most skilled preparators, a man well 
known over the country as the most expert of bird taxidermists. Mr. 
Wood was born in New York State in 1852. When about 27 years 
of age he was employed by Ward’s natural history establishment at 
Rochester, N. Y. Here, for the first time, his work was congenial and 
he made rapid advances in the general work which was assigned 
him. It was soon observed that he was especially interested in the 
mounting of birds, at which he would work in his own time after 
hours, and he was assigned as assistant to their best bird taxidermist. 
Deficient in natural mechanical ability, it was only after the most per- 
sistent effort that he finally reached the point where he could make 
