OOiMM 



Fig. 11.. Head end of the larva of 

 an undetermined monogenetic tre- 

 matode from the gills of Prognichtis 

 agoo (Schl. ) near the Banks of 

 Hokkaido (Pacific Ocean). 



O.fi, 



Fig. 12. Gyrodactylus elegans Nord.- 

 mann, adult worms from the gills of 

 Cyprinus carpio L. from pond farms 

 in the region of Alma-ata (Kazak, 

 SSSR). 



Fig. 13. Murraytrema robustum 

 (Murray), adult worm. Natural 

 size 2. 5 mm (According to 

 Murray, 1931). 



nunaber decreases in proportion to the complication of the muscular attaching 

 apparatuses (concerning the ones that are still developing, see the corres- 

 ponding section of the book). 



11 



