1894.] Zoology. 815 
As to the function of the gland, bearing in mind the observations of 
Stóhr and Killian on the tonsils, he concludes that the thymus exists in 
fishes for the protection of the gills from bacteria, etc., by the forma- 
tion of leucocytes. With the disappearance of the gills of fishes and 
perrennibranchiate amphibians, the gland undergoes a restriction in 
the area of its formation and its functions are transformed to other 
organs. In the higher vertebrates this protective function is trans- 
ferred to the tonsils at the opening of the respiratory passage. 
—F. C. Kenyon. 
