14 A CATALOG OF ILLINOIS ALGAE 



and counties from which the report was made. In the second 

 unit the county names are arranged alphabetically with the 

 proper data associated. This method simplifies the problem of 

 checking distribution within the State and will entail no particu- 

 lar difficulty to the student who wishes to know who made a 

 particular report of a species, since the only effort required will 

 be the association of the appropriate county names in the two 

 units of data. 



