114 ILLINOIS BIOLOGICAL MONOGRAPHS [114 



DESCRIPTION OF PLATE 



Fig. 90. — Cercaria micro pharyttx; ventral view. X 170. 



Figs. 91, 92. — Cercaria micro pharynx; ventral and lateral views of stylet. X 540. 



Fig. 93. — Cercaria micropharynx; distribution of glands. X 170. 



Fig. 94. — Cercaria micropharynx; sporocyst with non-localized germinal epithelium. X 



Fig. 95. — Cercaria micropharynx; cercariae encysted in old sporocyst. X 54. 



Fig. 96. — Cercaria micropharynx; genital cell masses. X 170. 



Fig. 97. — Cercaria micropharynx; transverse section thru brain center. X 540. 



Fig. 98. — Cercaria micropharynx; transverse section thru excretory cornua. X 540. 



Fig. 99. — Cercaria micropharynx; transverse section thru tail. X 540. 



Fig. 100. — Cercaria racemosa; ventral view. X 150. 



Figs. 101, 102. — Cercaria racemosa; ventral and lateral views of stylet. X 330. 



Fig. 103. — Cercaria racemosa; detail of salivary- glands. X 150. 



Fig. 104. — Cercaria racemosa; genital cell masses. X 330. 



Figs. 105, 106. — Cercaria racemosa; sporocysts, showing localized germinal epithelium and 



attachment organ, ao. X 54. 

 Fig. 107. — Cercaria racemosa; lateral view of genital cell masses in region of acetabulum. 



X 330. 

 Fig. 108. — Cercaria racemosa; optical view of the sporocyst in region of birth-pore, bp; arrow 



points toward attachment organ. X 330. 

 Fig. 109. — Cercaria trisolenala; ventral view. X 150. 

 Fig. 110. — Cercaria trisolenala; dorsal view of collar spines. X 170. 

 Fig. HI. — Cercaria trisolenala; lateral view of collar spines. X 330. 

 Fig. 112. — Cercaria trisolenala; sketch of acetabular spines. X 540. 

 Fig. 113. — Cercaria trisolenala; typical cj^stogenous cell glands, showing granules and chro- 



midia. X 540. 

 Fig. 114yl-£. — Cercaria trisolenala; sketches of developmental stages. X 80. 

 Fig. 115 A-C. — Cercaria trisolenala; stages in encystment. X 80. 



