314 RYDBERG: Rocky MOouNTAIN FLORA 
number 787, about 28 per cent. of the whole flora... Of the 
787, no less than 244 were proposed by Professor Aven Nelson 
himself; 152 are by Dr. Rydberg, of the New York Botanical 
Garden, and 148 by Dr. E. L. Greene, now of the U. S. National 
Museum, but at one time a resident of Colorado. ... The 
number of species accepted as valid is 2,733, while no less than 
1,788 specific names are rejected as synonyms or insufficiently 
known. Many of those latter were proposed by Professor Nelson 
himself, more by Rydberg and Greene.” 
Why should more (nearly 66 per cent. more) of Professor Nel- 
son’s species be acceptable and ‘‘many more’”’ of Dr. Greene’s and 
my own be reduced to synonymy? Not counting the time before 
the first edition of the Manual of the Rocky Mountain Region 
appeared, Dr. Greene published on the flora for ten years, between 
1885 and 1895, when practically no work was done by Professor 
Nelson or myself, and he has published at least twice as many new 
species from the Rocky Mountain Region as Professor Nelson. 
Both Dr. Greene and myself have had access to much larger her- 
baria and libraries than has Professor Nelson, and have seen speci- 
mens from the Rockies which he has not seen. The New Manual, 
therefore, seems to show a decided partiality for the species pro- 
posed by Professor Nelson himself. Some partiality would be 
expected, but in this case it seems out of proportion. Professor 
Nelson is a very conscientious worker, and it would be unjust to 
claim that this imparity in treatment was intentional. The main 
cause, I think, is that he had not seen the types or authentic 
material of many of the species so reduced. He knew his own 
species, but not all of those proposed by other botanists. It was 
not fair to them simply to reduce their species to synonymy, if 
such species were unknown. If question-marks had been added to 
show probable synonymy, the matter would have been improved 
considerably. There are many cases in which I am confident 
that Professor Nelson had no specimens illustrating species reduced 
to synonymy. 
Some years ago I spent considerable time on Erigeron as repre- 
ented in the Rockies and had seen the type or a duplicate of the 
type of nearly every species described. In fact, I knew the genus 
(one of the largest in the region) as well as any of the composite 
genera. That I should have resumed the work on that genus just 
