80 ILLINOIS BIOLOGICAL MONOGRAPHS [526 



EXPLANATION OF PLATE 



Mature redia of Ccrcaria trivolvis. X 88. 



Immature redia of Ccrcaria trivolvis. X 88. 



Mature Cercaria trivolvis, ventral view. Cystogenous glands not shown. 



X 195- 

 Cercaria rubra freed from cyst, ventral view. X 195. 

 Cercaria rubra inside of cyst. X 195. 

 Anterior end of Cercaria rubra, dorsal view. X 195. 

 Cercaria reflexae, ventral view. Cystogenous glands not shown. X 88. 



