well-kno\vn Polystoma integerrimum Froelich the transition from a single 

 rounded testis to such a foUicularly-merged one takes place during the on- 

 togeny by way of the considerable growth and individualization of separate 

 parts. 



p. 59 



Fig. 81. Calicotyle kroyeri Diesing, Fig. 82. Polystomoides ocellatus 

 adult worm from ^he skin rear the anal (Rudolphi), adult worm from the 

 opening of Raja batis L. n'.ar the anterior part of the esophagus of 



southern shores of England (Atlantic Emys orbicularis (L. ) from the 

 Ocean). Four eyes are visible on neighborhood of Poltava, 



the buccal sucker. 



Usually the testes are located in the po^Lerior half of the body 

 behind the ovary but there are types ii which the-' lie mainly in the anterior 

 part even though some may partially extend beyor d the ovary. Among 

 Cyclobothrium sessilis (Goto) numerous testes are located in the proximity 

 of the sex pore. Their number is more or less the same both in front of 

 the ovary and behind it (Fig. 86). Among Diclidophora pollachii (Beneden 

 and Hesse) the testes are located generally in the same way as in the 

 preceeding species, but the number of testes lying closer to the anterior 

 part is almost twice as large as those lying behind the ovary (Fig. 87). 

 Annong Octoplectanocotyle trichiuri Yannaguti, the number of testes 'yi'^g 

 in front of the ovary is also larger than those lying behind (Fig. 88). 

 Finally, among Protomicrocotyle pacifica Meserve, all the numerous l, tes 

 lie in front of the ovary (Fig. 89). The distribution of the testes in the depth 

 of the body varies: they either lie in the middle between the ventral and 

 dorsal surface, or closer to the ventral side. In separate cases, the testes 



60 



54 



