NEMATODE PARASITES OF BIRDS 



21 



Male 10 to IT mm. Ion*: by 250 to 350/x wide. Bursa (fig. 14) with 

 2 large lateral lobes and a small median lobe. A pair of lame con- 

 tinuous papillae on the posterior lip of the cloacal aperture. Ventro- 

 ventral ray small, its tip ending at an incision in the bursal margin. 

 Latero-ventral ray longer, enlarged proximally, its tip ending at an 

 incision in the bursal margin. Externo-lateral ray short, the tip not 

 near the bursal margin. Medio-lateral ray long, extending almost 

 to bursal margin. Externo-dorsal ray long and thick, originating 

 near the base of the common stem from which all rays in the lateral 

 lobes arise, and not extending to near the bursal margin. Dorsal ray 

 short, bifurcating posteriorly and the bifurcations forked and ter- 

 minating in 2 tips; this ray alone has an independent origin. The 



Figs. 13-16. — 13, Amidostomum ansekis. Anterior end. 14, Same. Male 

 . bursa. Xos. 13-14 after Railliet, 1893. 15, Amidostomum raillieti. An- 

 terior end. 16, Same. Bursa op Male. Nos. 15-16 after Skkjabin, 1916 



maroon-colored spicules are 200/x long (Skrjabin says 280 to 300//.) 

 and slender and are cleft near their middle; the internal branch ends 

 in a spatulate tip ; the gubernaculum is slender and 95/x long. 



Female 12 to 24 mm. long. The body is slender anteriorly, widens 

 at the vulva to 300 or 400^, and thins abruptly behind the anus; the 

 tail is long and straight and bluntly pointed. The vulva is a trans- 

 verse slit, 160jm long, Vr, of the body length from the tip of the tail, 

 and is sometimes covered with a projecting appendix. The eggs are 

 thin-shelled, 85/x, long by 50/x wide, or, according to Skrjabin, 110/i 

 long by 82/a wide, (or 100/x, by G6ju in American material) and con- 

 tain an embryo when deposited. 



Life history. — Unknown; probably simple and direct. 



Distribution. — Europe, Asia, Africa (Algeria) and North America 

 (United States). 



