104 BULLETIN 69, UNITED STATES NATIONAL MUSEUM. 



armed with strong spines. Testicles numerous, in median field. 

 Female organs median, a single set in each segment. Uterus forming 

 a cage-like meshwork consisting (Fuhrmann, 1908a, p. 88) of a dorso- 

 ventral ring with dorso-ventral anastomoses. Accessory vagina 

 opening ventrally, communicating (?) with a canal from the excretory 

 system opening in the ventral surface of the segment in the median 

 line. Adults in birds. 



Type-species. — Amahilia lamelligera (Owen, 1832) Diamare, 1893 



Genus SCHISTOT^^NIA Cohn, 1900. 



Generic diagnosis. — Amabiliidse: Scolex with very large, armed 

 rostellum. A single set of reproductive organs in each segment. 

 Male genital pores irregularly alternate. Male deferent canal passes 

 between the longitudinal excretory vessels. Testicles numerous, 

 extending across the entire width of the segment. Vagina absent. 

 Vaginal functions performed by a median, dorso-ventral canal (acces- 

 sory vagina) opening on the surface of the segment dorsally and 

 ventrally. Adults in birds. 



Type-species. — ScJiistotsenia macrorJiyncha (Rudolphi, 1810) Cohn, 

 1900 = Scliistot8enia scolopendra (Diesing, 1850). (See Fuhrmann, 

 1907b,, p. 534.) 



SCHIST0T.S;NIA MACRORHYNCHA (Rudolphi, 1810) Cohn, 1900. 



For description see Krabbe, 1869b, p. 305, pi. 7, fig. 172 (Tsenia macro- 

 rhyncha). — Cohn, 1900c, pp. 265-277, pi. 14, figs. 8-18 (S. macrorhyncha and 

 S. scolopendra).— ChKRC, 1907, pp. 704-708, pi. 1, figs. 3-7. 



Hosts. — Golymbus dominicus, Golymhus auritus. 



Genus TATRIA Kowalewski, 1904. 



Generic diagnosis. — Amabiliidse: Rostellum with a single crown of 

 few large hooks at apex and with numerous rows of small spine-like 

 hooks behind the crown of large hooks. Suckers and posterior por- 

 tion of head covered w^ith minute spines. Segments not numerous 

 (about 30). A single set of reproductive organs in each segment. 

 Male genital pores regularly alternate. Cirrus pouch large. Tes- 

 ticles not numerous (7 in the type species). Male and female canals 

 pass between the longitudinal excretory vessels. Distal end of 

 vagina instead of opening to the exterior turns backward into the 

 next following segment and opens into the seminal receptacle of that 

 segment. Seminal receptacles in median line of strobila. An 

 accessory vagina present in the opposite side of the segment from the 

 cirrus pouch, sometimes with an opening in the margin of the seg- 

 ment. Adults in birds. 



Type-species. — Tatria hiremis Kowalewski, 1904. 



J 



