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REVIEWS 



Rydberir's Flora of the Rocky Atountalns * 



It is remarkable that although all parts of the United States 

 have been settled now for many years, and most of the states 

 explored rather thoroughly, botanically, no flora of the whole 

 country has ever been published, if we except the fragmentary 

 works of such early writers as Michaux, Pursh, and Nuttall. 

 Indeed, only two serious attempts at a United States flora have 

 ever been initiated, that of Torrey and Gray, some eighty years 

 ago, and the comparatively recent Synoptical Flora, begun by 

 Dr. Gray — neither of these ever brought near completion. 

 This lamentable lack has been partly compensated for by the 

 numerous regional manuals and by a host of state floras, some 

 of them descriptive. With the appearance of Dr. Rydberg's 

 long-awaited Flora of the Rocky Mountains, the regions for 

 which a more or less adequate published flora exists are so ex- 

 tended that only two states are left unprovided for — Nevada and 

 Arizona. 



Of the two floras of the Rocky Mountains previously pub- 

 lished, the first, by Coulter, appeared in 1885, and has long been 

 so out of date as to be useless. The second, by Coulter and 

 Nelson, appeared in 1909; it is an admirable work, so far as 

 Wyoming and the immediately adjacent regions are concerned, 

 but it is less satisfactory for the more remote districts. The 

 present work covers a much larger region than either of its 

 predecessors, its area extending from Saskatchewan, western 

 Nebraska, and Colorado to eastern British Columbia, Idaho, and 

 Utah, and it will be found to cover satisfactorily eastern Wash- 

 ington and Oregon, as well as the mountains of northern New 

 Mexico. Several states and provinces now for the first time 

 have a descriptive flora available — Utah, Idaho, Saskatchewan, 

 and Alberta. 



* Flora of the Rocky Mountains and adjacent plains — Colorado, Utah, Wyo- 

 ming, Idaho, Montana, Saskatchewan, Alberta, and neighboring parts of Nebraska, 

 South Dakota, North Dakota, and British Columbia. By P. A. Rydberg, Ph.D., 

 curator, New York Botanical Garden, pp. i-xii, i-iiio. New York, December, 

 191 7. Published by the author. 



