Bull. U. S. B. F., i.)1';---o. 



Plativ X\'. 



Fro. I. — Gil! of a black bass infected with alochidia of 

 mucket, havit^sili^ Ugavieniina. 



.jS^^ 



'K- 



^ 

 ^ 



^! 



i 



.-i 



Fig. s. — Three gill filaments of rock bass, willi plochitHa of 

 mucket, 



Fig. 2. — Part of fig. i, enlarged. 





1 I' rniatiou of cyst surrouudiu-; a .;,luchidiuni ul Ihe mucket. Taken at i , minutes, 30 minutes, i hour, 

 and 3 hours, respectively, after infection. 



%„*2<^ 



Fig. 5.— Young mutkets, one week after liberation from Ihe fish, showing new 

 growth of shell, cilia on foot, and positions assumed in crawling. Enlarged. 



Fig. 6. — Young Lake Pepin muckels at 

 ages of I, 2, 3, and 4 months, respec- 

 tively. X'atural size. 



fFigs. i-s after Lefevre and Curtis.] 



