Vili 



Contents. 



Pag. 



Chapter 7. A Systematic Guide to the 

 Genera and Species of Rlrizocephala, with 

 anatomical Diagnoses 106 



Peltogaster 109 



Parthenopea 110 



Sacculina 110 



Heterosaccus 113 



Lernaeodiscus 114 



pag- 



Triangulus 115 



Sylon H6 



Clìstosaceus H7 



Duplorbis 118 



Apeltes 122 



Thompsonia 122 



Thylacoplethus 122 



List of Literature 123 



