76 ILLINOIS BIOLOGICAL MONOGRAPHS [522 



EXPLANATION OF PLATE 



Fig. 23. Mature Cercaria diastropha, dorsal view. Cystogenous glands not shown. 

 X 88. 



Fig. 24. Free hand drawing of Cercaria diastropha from the side. X 75. 



Fig. 25. Redia of Cercaria diastropha. X 88. 



Fig. 26. Cercaria caryi, ventral view. From Cary's material. X 140. 



Fig. 27. Cercaria megalura, ventral view. From Cary's material. X 140. 



Fig. 28. Diplodiscus temporatus, ventral view. From Cary's experimental tad- 

 poles. X 140. 



