Toit] CURRENT LITERATURE 395 
based on the general character of the stems, leaves, and inflorescence. About 
50 of the species recorded are new to science. The excellent keys, full descrip- 
tions, and numerous habital and detailed illustrations render this an exceed- 
ingly pierre treatise on a most difficult but highly interesting group of 
plants—J. M. GrEENMAN, 
The Australian pines.—An elaborate volume records the results of the 
labors of BAKER and SmirHs in studying the “pines of Australia.” Curiously 
enough, there are no pines in Australia, the Abietineae being the only one of 
the six tribes of conifers unrepresented. The feature of the book is the wealth 
of illustrations, almost all of which are reproductions of photographs, many 
of which were made by the natural color process. The technical skill: shown 
in this photographic work is to be highly commended, and probably in no 
other publication have conifers such a setting. The siete m sane oe is 
confessedly economic, and this aspect of the Australia 
sented with a completeness that leaves little to be desired. It seems that 
Callitris, next to Eucalyptus, is the most important genus of Australian trees; 
and the authors have indicated its complete generic separation from Wid. 
dringtonia of South Africa and Tetraclinis of North Africa, which makes it a 
genus restricted to Australia and Tasmania. In presenting the eleven genera 
of the region, the authors include so many details of structure and of pr 
ucts that the volume is a thesaurus of observations for those who are in a 
Position to estimate their value. In the presentation of each species, after 
an account of its history and its taxonomic characters, there are described 
ully the economics, anatomy, and chemistry of leaves, fruits, timber, and 
bark.—J. M. C. 
Conservation.—Because of the loose ae Hise: TTS the conser- 
vation of our resources, it is well to have a t reatise on the subject 
by one of acknowledged competence. se a treatise is i one from the hand 
of President Van Hise of the University of Wisconsin,‘ which is based on 
lectures before students. Botanists will be interested especially in the 
chapter on forests, and in the one on land, in which soil conservation is con- 
sidered. The author’s expert training as a geologist fits him peculiarly for 
his consideration of the mineral resources, and scarcely less so for his treat- 
ment of the soils. The final chapter deals with conservation and mankind, 
and there are three appendices, which give declarations of conservation prin- 
ciples as set forth by various organizations.—H. C. CowLes. 
‘ Baker, Ricuarp T., and Suira Henry, G., A research on the pines of Aus 
tralia. Technological Masai. New South Wales. 4to. pp. xiv-+458. figs. 300. maps 
3. Sydney: Government Printer. 1910. 
* Van Hise, C. R., The conservation of natural resources in the United States. 
2 
8vo. pp. xiv-+413. pls. 16. New York: The Macmillan Co. 1910. $2.00. 
