Addendum: page 23, Life of Inland Waters, second 

 edition. 



In the revision of the map and list of American 

 biological field stations for the second edition of this 

 book the University of Michigan Station at Douglas 

 Lake was, by a singular oversight, omitted. It is men- 

 tioned in the text on page 70. It is one of the largest 

 and most important centers of fresh-water investigation 

 in America. 



