BVLL. U. S. B. F. igi2. 



Plate XCVIII. 





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Hl<;. 98. — Marked hyperplnsia domesticated brook trout used as control for figrure 99. Fish 1070. table ix. X86. 



Fig. 99. — Fisli from same lot treated b> addiiiy; iii <' >miTuious concentration potassium iodide in the water 1 : 5. tJ<X).LK.l'.t. 

 Marked regression of hyperplasia at the end of J7 dins. 1 ish KI69, table ix. X86. 



