NEMATODE PARASITES OF BIRDS 



17 



ORMTHOSTRONGYLUS HASTATUS (Linstow, 1905) Tr.ivassos, 1920a 



Synonym. — Strongylus hastatus Linstow, 1905. 



Hosts. — Lyrurus tetrix {Tetrao tetrix). 



Location. — Intestine. 



Morphology. — Ornithostrongylus (p. 11): Cuticle transversely 

 striate and with a lateral cephalic ala originating 230/* from the head 

 end. Head with 6 rounded papillae. Buccal aperture leads into a 

 vestibule with parallel walls and 78/* deep. Esophagus 5/32 of body 

 length or about 100 to 300^ long. Excretory pore at level of posterior 

 third of esophagus. 



Male 8.7 mm. long by 190/* wide. Bursa (fig. 12) with 3 lobes, the 

 dorsal small but sharply defined. Ventral rays close together and 

 parallel ; the posterolateral set off from the medio-lateral and ex- 

 terno-lateral, which are close together and parallel ; the externo- 



Figs. 11-12. — 11, Ornithostrongylus papu.latus. Male bursa. After Linstow, 

 1882. 12, Ornithostrongylus hastatus. Male bursa. After Linstow, 1905 



dorsal close to and parallel to the externo-lateral most of its length, 

 but diverging distally; the dorsal with a long stem bifurcating near 

 its tip and with 2 small external branches near the bifurcation and 

 extending to incisions in the dorsal lobe. Spicules 220/* long, each 

 terminating in a lancetlike prolongation which is enlarged in its 

 median portion. 



Female 21.5 mm. long by 530/* wide. Vulva near the posterior 

 extremity. Eggs thick-shelled, 30/* by 21/* in diameter. 



Life history. — Unknown; probably simple and direct. 



Distribution. — Europe. 



Family AMIDOSTOMIDAE Baylis and Daubney, 1926 



Family diagnosis. — Trichostrongyloidea (p. 7): Forms with a 

 reduced buccal capsule present; in forms with the capsule much re- 

 duced or, according to Skrjabin. absent, the head has 4 papillae or 

 papilliform lips and 2 epaulets. 



Type genus. — Amidostomum Railliet and Henry, 1909. 



