But. U. vS. B. F., 1908. 



Plate LXXXIII. 



13.— Series of covered trout-hatching troughs at White Sulphur Springs station (West Virginia) 

 equipped with the Robinson pan aerator. (See p. 716.) 



Fig. 14— Trout-hatching troughs witli Merrill 1 : u.n,- tone. (See p. 717.) Show-S alw) tray lia.sket of a pattern 

 used at some trout stations, much deeper than ordinary tray and intended to liold fry after liatching. Left 

 trough with tray removed to show shower of water produced by aerating cone. 



