ECOLOGICAL WORK IN BOTANY. 
203 
noteworthy contribution to the knowledge of our plants, repre¬ 
senting the results of fifty years' collecting and study. It was fol¬ 
lowed by another valuable piece of work upon the flora of Ala¬ 
bama by Dr. Chas. Mohr, representing the results of forty years’ 
study. The book includes a discussion of the plant societies of 
the state as well as the general physiognomy of the flora. 
There are numerous other monographs dealing with the flora 
of particular regions, but time and space will permit only the 
mention of a few: Lindheimer, Plants of the Mexican Boundary; 
Coulter, Manual of the Rocky Mountain Region; Coulter, Botany 
of Western Texas; Watson, Botany of California; Howell, Flora 
of the Northwestern United States; Britton, Flora of New Jer¬ 
sey; Beal, Flora of Michigan; Millspaugh, Flora of West Vir¬ 
ginia; Dudley, The Cayuga Flora; Brainerd, Jones and Eggleston, 
Flora of Vermont. 
Such observations as the above, if carefully made, are worth 
much for the student of plant distribution. By an extension of 
this work the time is drawing near when we shall have the ma¬ 
terial necessary for a comparative plivtogeographical study of 
the entire country. 
A large and noteworthy contribution to the botany of this 
country was made by Coville in his study of the flora of Death 
Valley, California. Although most of the work is from the stand¬ 
point of the systematist, yet it gives us a picture of xerophytic 
plant life and the conditions it has to meet. 
The Phytogeography of Nebraska was the subject of an ex¬ 
tensive and interesting study of the plant life of that state by 
Pound and Clements. It is an attempt to study the distribution 
of plants in that state, not according to localities, but according 
to factors of the environment. Notwithstanding more or less of im¬ 
perfection it represents some of our best work in recent ecology. 
The ideas first presented there are now being worked out with 
more completeness by Dr. Clements in his studies on the vegeta¬ 
tion of the Rocky Mountains in Colorado. 
The problems of succession and invasion on sand dunes and in 
river valleys have been studied and very completely described 
by Cowles. His work is important in bringing out the dynamic 
relations of different societies. 
