236 ILLINOIS BIOLOGICAL MONOGRAPHS [524 



EXPLANATION OF PLATE 



Fig. 104. Cyathocephalus americanus, diagram of median sagittal section. 



Fig. 105. Bothriocephalus scorpii, portion of section, showing union of vagina with oviduct. 



Fig. 106. Bothriocephalus cuspidatus, young egg, showing an early stage in development, 

 drawn from life. 



Fig. 107. Bothriocephalus cuspidatus, older egg, many-celled stage. 



Fig. 108. Clestobothritim crassiceps, four consecutive sections thru union of vagina and ovi- 

 duct, showing the receptaculum seminis. 



Fig. 109. Abothrium rugosum, union of vagina and common vitelline duct with oviduct. 

 The reference line is 0.02nim. long. 



