344 THE AMERICAN NATURALIST. [VoL. XXXVI. 
the recognized trees and shrubs of his district. It is pleasing to read 
that the high school possesses an arboretum in which practically all 
of the species are cultivated. 
The relation of forests to snow is discussed by Carpenter in 
Bulletin No. 55 of the Colorado Experiment Station, illustrated by a 
series of photograms from excellent negatives. 
In paper, presswork, and general appearance the third annual 
report of the New York State College of Forestry, recently distributed, 
is more like a product of the British colonies than of the United 
States. 
The value of growth rings in the so-called exogenous trunk, as an 
index of age, is considered by Roger in the Revue Horticole of 
January zr. 
The distribution in Iowa of twenty native forest trees is discussed 
by Professor Bessey in T'he Forester for December. 
The big trees of California are the subject of a well-illustrated 
article by R. T. Fisher in Zhe World’s Work for February, which 
also contains illustrated articles on the cultivation of tobacco under 
cloth in Connecticut and the growing of olives in California. 
What the cedar of Lebanon may become in cultivation is shown 
by photograms in the Gardeners’ Chronicle for January 4. 

` PETROGRAPHY. 
Tillman's ** Text-Book of Important Minerals and Rocks,” ' is 
an attempt to present to the student a brief account of the character- 
istics of the common minerals and rocks. The plan of the book is 
good. It discusses the elements of geometrical crystallography in 
24 pages, in which only the most fundamental forms of the six sys- 
tems are described. The physical and chemical properties of 
minerals are discussed in the next 5 pages. Then follow 65 pages 
devoted to the description of about seventy-five of the commonest 
mineral species, and about 4o pages in which the descriptive 
material is embodied in tabular form. The final 22 pages treat of 
the commonest rocks. 
lTillman; S. E. A Text-book of Imp Minerals and Rocks. With tables for 
See one "Ner Yorks, John Wiley & Sons, 900 186 pp. 
35 


