THE VEGETATION OF THE ALPINE REGION OF THE ROCKY MOUNTAINS IN 



COLORADO. 



By Theodore Holm. 



(With plates 1-7.) 



INTRODUCTION. 



With the object in view to present a sketch of the Alpine flora in Colorado, I have naturally 

 felt induced to compare this with the Arctic, since no small number of species are common to 

 both regions. The material upon which my observations are based was collected by myself in 

 Colorado during the summers of 1896 and 1899, from the beginning of July to the middle of 

 September. The mountains as follows were explored: The mountain range along Clear Creek 

 Canyon from Golden City to the headwaters, including Torreys Peak, Grays Peak, and Mount 

 Kelso; James Peak near Central City; Longs Peak near Estes Park ; Mount Massive and Mount 

 Elbert near Leadville; Pikes Peak; furthermore Thompsons Canyon on Longs Peak, which is 

 located so as to contain a purely Alpine vegetation. The altitude of the Alpine region lies 

 between 3,350 and 4,300 meters. 



Moreover, I have had the opportunity to visit the polar regions as the naturalist of the 

 Danish Dijmphna Expedition to the Kara Sea in the years 1882-1883, and as the naturalist of two 

 Danish expeditions to Greenland in 1884-1886 under the auspices of the Danish Government. 



Having thus had the opportunity to study the Arctic as well as the Alpine flora, I thought 

 a comparison of both might prove useful to solve the question relative to the origin of these 

 floras, and especially with reference to the singular, geographical distribution of certain species, 

 which, so far, has been explained in different manners. Beside discussing the geographical 

 distribution, I have also given much attention to the vegetative structures of these plants, and 

 the drawings, which I have inserted, may give the reader some idea of the aspect of some of 

 these high- Alpine types. 



Dr. E. L. Greene identified most of the Compositae; Dr. W. J. Beal some of the Gramineae, 

 and Dr. P. A. Rydberg has kindly named the Salices and Potentilla. My Arctic herbarium was 

 augmented very considerably by the liberal gifts of the Swedish Riks-Museum through Dr. 

 C. A. M. Lindman, and of the Canadian Geological Survey through my friend, the late Mr. James 

 M. Macoun. 



