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



Plate XCIV. 



Fig 90.— I,ow power section at median line through thyroid region of wild Wisconsin brook trout, showing well- 

 aevelopea carcinoma of the thyroid infiltrating surrounding structures, bone and cartilage. After 18 months raw liver 

 feeding at Craig Brook, Experimental induction of carcinoma of the thyroid, X13 



