BuL. U. S. B. F., 1908. 



Plate I.XXXII. 



Fig. II. — Field hatchery at Grand Mesa I,ake.s. Colorado. Blackspotted trout eggs to the number of 7,000,000 

 in one season have been developed liere to the eyed stage with only a normal loss. 



3. 12.— Tray of trout eggs in hatching trough. The fry fall or work through the rectangular mesh of the tray bottom 

 into the trough, where they are visible at the left of this picture. Trav is wedged at proper depth in trough during 

 incubation, and, for convenience in removing dead eggs from time to time, may be floated by releasing the wedges 



