HOW TO USE THE KEYS 21 



To the Key of the tribe just found, and use it in the same 

 way until the name of the genus is found, when it is 

 time to turn 



To the key of the genus, if there arc more than one species 

 of that genus in the State, and find the specific name in 

 the same way. The name of the grass is the genus 

 (generic) name and the species (specific) name corri- 

 bined as a man's name is, except reversed — as Smith 

 John instead of John Smith. Following the key of the 

 species will be found a list of the species of that genus 

 with the full name of each followed by (1) an abbrevia- 

 tion of the name of the man or men who named it; (2) 

 the common name if it has any; and (3) a statement 

 of its distribution in the State. If this latter statement 

 does not agree with the facts concerning the grass in 

 hand the determination is probably incorrect or a grass 

 has been found that is not included in the list. Special 

 care has been taken to include all species of which col- 

 lections have been made, but a few may have beer 

 omitted and there are doubtless some species growing 

 in the state that have not been collected, though they are 

 probably very rare. After determining the species, the 

 student should turn 



To the general discussion of that genus which precedes 

 the key to the tribe in which it belongs. If it is a com- 

 mon grass he will probably find some confirmatory evi- 

 dence of the correctness of his determination and what 

 data are to be had on the economic importance of that 

 grass and will know the most of what is known about 

 it. He is warned not to allow the common name to have 

 much weight in settling questions. For technical 

 descriptions of the species the student is referred to the 

 various Manuals of botany, such Coulter's Manual of 

 Western Texas, Small's Flora of the Southeastern 

 States, Coulter and Nelson's New Manual of the Rocky 

 Mountains. fRvdberg's Flora of Colorado only has keys 



