PARASITIC FLATWORMS 



445 



92 (89) Root of cirrus with one or two pairs of powerful hooks lying in 

 special pockets; genital canals pass between longitudinal 

 excretory vessels. 



Gryporhynchus Nordmann 1832. 

 (Syn. Acanthocirrus Fuhnnann 1907.) 



Genital canals pass between the longitudinal excretory vessels. 

 In genital atrium lateral to root of cirrus two special pockets with one 

 or two pairs of powerful hooks in each. Uterus sac-like. Adults in 

 birds. 



Three species or more in herons; not reported from North America. 



FIG. 752. Gryporhynchus cheilancristrotus. Proglottid with contracted 

 cirrus-pouch; short heavy hooks in pockets at opening of cirrus-pouch into 

 genital cloaca. Magnified. (After Clerc.) 



93 (86) Genital pores not unilateral but alternating 94 



94 (97) Genital pores regularly alternating 95 



95 (96) Rostellum with single crown of hooks. Less than 30 proglottids; 

 scolex large; no neck Amoebotaenia Cohn 1899. 



Proglottids much broader than long. Testes rather numerous (12 or more), in posterior 

 portion of segment. Uterus sac-like, fills entire medullary portion of terminal proglottids. 

 Adults in birds. 



Four or five species, some in shore birds that occur in North America. 



FIG. 753. Amoebotaenia. 

 Anterior end, magnified. 

 (After von Linstow.) 



FIG. 754. Amoebotaenia cuneata. a, dorsal view; 

 b, ventral view; magnified. (After Cohn.) 



96 (95) Two rows of hooks on rostellum. 



Cy cluster a Fuhrmann 1901. 



Rostellum with double crown of hooks. Longitudinal musculature in three layers. Geni- 

 tal canals pass between the longitudinal excretory vessels and open into a very muscular cloacal 

 canal. Testes numerous, scattered throughout entire dorsal medullary portion of proglottid. 

 Ovary and yolk gland surrounded by ring-like uterus with secondary branches. Eggs with 

 two shells. Adults in birds. C. capita, the type species, is reported by Ransom as found in 

 the roseate spoonbill in North America. 



97 (94) Genital pores alternate irregularly 98 



