78 ILLINOIS BIOLOGICAL MONOGRAPHS [524 



EXPLANATION OF PLATE 



Fig. 29. Cercaria megalura before the extrusion of cystogenous material, ventral 



view. X 195. 

 Fig. 30. Cercaria megalura after the extrusion of cystogenous material, ventral 



view. X 195. 

 Fig. 31. Mature redia of Cercaria megalura. X 88. 

 Fig. 32. Cross section of tail of Cercaria megalura. X 433. 

 Fig. ^- Cross section of Cercaria megalura before the extrustion of cystogenous 



material. X 276. 

 Fig. 34. Cross section of Cercaria megalura after the extrusion of cystogenous 



material. X 276. 

 Fig- 35- Cross section of immature redia of Cercaria megalura. X 433. 

 Fig. 36. Immature redia of Cercaria megalura. X 88. 



