Bull. U. S. B. F. 191 2. 



Plate CI. 





V. 











^i0&^' 















«; ^::>.»^ 







Fir.. 1115. — Domesticated brook trout from tlie 

 contimious flow to the water in the proportion of 1 :: 

 to the nonnal type. Fish 1084. table xii. X86. 



same lot ns fiEure 1"4. treated with bichloride of mercnr>' a«lde<l b\ 

 .OUO.UUU for 14 da>s. Disappeaieuce of hyperplasia. Marked reversion 



