Bull. U. vS. B. F., 1919-20. 



Plate XIX. 



Fig. I. — A fioatiug crate coutaiuiug luur baskets iu which fish infected with glochidia were placed aud young mussels reared. 



(Compare PL V, fig. 3.) 



l-'lG. 2. — Lilting one vi the baskets truiii the crate fur c.\aiiiinaliuii aud cleauiuy. 



