19 
periods, rather than being due alone to the difference in the mean 
air temperature. It is impossible in so short a notice to bring 
to the attention of the reader all the many points of interest in 
this publication which merits a careful perusal.—H. M. К. 
Professor Peirce in the October Popular Science Monthly dis- 
cusses the relation of civilization and vegetation. Civilization, 
he says, in "the form of agriculture plays sad havoc with natural 
native vegetation, destroying, driving back, exterminating most, 
domesticating and assimilating few, plants." Incidentally, in 
referring to the disappearance of the wild races from which our 
domesticated forms have arisen as due to assimilation he asks, 
“What is the joy of living as a tame hen, as a domesticated cow, 
as a pruned pear tree? ‘The ox that treadest out corn’ is sure 
of daily food; so is ‘the cock of the walk’; so also are the sub- 
jugated plants of farm and garden; but individuality has been 
sacrificed for safety." 
The article also discusses the injury to plants from air and 
soil gases, smoke, and cement rust.—J. B. 
THE Monarpas: A PHYTOCHEMICAL STUDY by Miss Wakeman 
appeared as Part 4 of Volume 4 of the Science Series of the 
Bulletin of the University of Wisconsin. Now and then one has 
the pleasure of reading a publication of this type in which the 
problem of the relations of a group of morphologically similar 
plants are attacked with chemical tools and it is found that the 
chemical relationships are also close. The genus Monarda con- 
tains several representatives and all are found in North America. 
Many of the species have bright colors and agreeable aromatic 
odors, so were early used by the first settlers and probably also 
by the Indians as “medicine” in the treatment of disease. The 
species are widely distributed and they go under a number of 
different local names. 
The red pigment of the brilliant M. coccinea (didyma) was 
studied as early as 1832. Later, other chemists examined the 
