Bull. U. S. B. F. 1912 
Plate LXVII. 
Fig. 29. — Frook trout sliowiiig- nodular growths in Fig. 30. — Brook trout showing numerous tumor vege- 
floor of moutli. tatioiis in floor of moutli. 
P^iG. 31. — .Section of floor of mouth showing thyroid follicles growing in epithelium above basal membrane. X70. 
P'ig. 32. — .Section from floor of mouth showing histological structure of papillary growths found in floor of mouth 
illustrated macroscopically by figure 30. X94. 
