INTRODUCTION. 
xv 
odicals; (2) in this catalogue there could not very well be given a 
fuller synonymy with citations of places of publication, nor fuller 
discussions, which are always desirable and often necessary for 
clearness sake; (3) if the diagnoses of new species had been inter¬ 
polated here and there, the uniformity of the catalogue would have 
suffered. 
As it is, the Flora is the result of much labor and stands as a brief 
index of the present knowledge of the flora of the state. In its 
present form, the author hopes that it will be valuable for the pur¬ 
pose for which it was prepared, viz., as a record of the higher vegeta¬ 
tion of the state of Colorado as far as known to-day and as a guide 
and help to those interested in its flora. Whatever shortcomings 
there may be, the author hopes will be forgiven. The technical sys- 
tematist will undoubtedly find many facts omitted which he would 
expect to find in a “ Flora of Colorado.” 
From the summary given after the catalogue it can be seen that 
the higher vegetation (fernworts and flowering plants) of Colorado 
comprises over 700 genera and 2,900 species, a number sur¬ 
passed only by California and perhaps by Florida out of all states 
in the Union. The largest families are Carduacece or the Composites 
proper, with 568 species or about igY% of the flora; Poacece or 
grasses, 267 species or 9%; Fabacece or Pea Family, 185 or 6^3% ; 
Brassicacce 144, Rhinanthacece 106, Cyperacece 101, Polygonacece 94, 
Rammculacece 92, and Rosacea 89 species, or between 3% and 4%, 
etc. Just as remarkable as the large number of species of Compo¬ 
sites (about Ys of the whole flora), is the small number of Pterido- 
phytes. The ferns proper are only 25, to which are to be added 15 
other fernworts. The same may be said of the Gymnosperms, only 
20 in number. 
The author has had the help of several specialists in certain groups. 
Professor L. M. Underwood has prepared the manuscript of the 
Pteridophyta, and Mr. H. D. House that of the family Violacece. 
Mr. G. V. Nash has given valuable assistance in the grasses. 
The account of the Polygonacece was written in conjunction with 
Dr. J. K. Small. Dr. Theodor Holm has characterized the groups 
and species of Carex and listed the specimens of that genus, while 
the author prepared the key to the groups. Mr. S. H. Burnham, 
Mr. H. D. House and Mr. W. W. Eggleston have assisted in listing 
the localities and Mrs. William Mitchell in copying the keys. 
P. A. Rydberg. 
New York Botanical Garden, 
New York, March, 1906. 
