316 



BULLETIN 140, UNITED STATES NATIONAL MUSEUM 



Life history. — Unknown ; probably involves intermediate stages in 

 other hosts. 



Distribution. — South America (Brazil). 



THELAZIA STEREURA (Rudolphi, 1819) Railliet and Henry, 1910 



/Synonyms. — Spiroptera stereura Rudolphi, 1819; ? Oxyspirura 

 stereura (Rudolphi, 1819) Ransom, 1904. 



Fig. 378.- — Thelazia lutzi. Male tail. After Travassos, 1918 



Hosts. — Primary : Buteo vulgaris, B. vulpinus, Falco naemus 

 (=AquUa naevia=A. maculata) ; secondary: Unknown. 



Location. — Under nictitating membrane and in auditory meatus. 



Morphology. — Thelazia (p. 311) : Body thick, attenuated ante- 

 riorly with the head end truncate. Cuticular annulations with nu- 

 merous small campanuliform folds. Head (fig. 379 a) without mem- 

 branous appendages. Mouth orbicular, without lips. According to 

 Skrjabin's figure, the cuticular striations do not cross the lateral lines 



Fig. 379. — Thelazia stereura. Female, u, Head end, showing 

 vdlva ; b, tail. After Skrjabin, 1922 



but leave a smooth area there; the lateral lines end at the level of 

 the anus. 



Male 12 to 15 mm. long by 800/x wide. Tail coiled once spirally ; 

 no caudal alae. Posterior extremity extended into a short appendage 

 with knob like end. Two unequal spicules ; the short one styloid, 

 with a sharp point, and the long one filiform. Schneider states that 

 there are more than 4 pairs of preanal papillae. 



Female 12 to 18 mm. long by 1 mm. wide. Two lateral cervical 

 spines. Buccal cavity 51/* deep by Q8/x wide in large specimens. 

 Esophagus 34(V long. Tail (fig. 379&) straight, acutely conical, 

 prolonged into a styloid appendage with a rounded knoblike end; 



