Bull. U. S. B. V., 1919-20. 



Platr XIX. 



Fig. : 



-A floating crate containiug (our baskets in which fish infected with glochidia were placed and young mussels reared. 



(Compare PI. V, fig. 3.) 



Fig. 2. — LiUiug one of the baskets from the crate fur exaniiiiatiou ami t. leaiii 



