NEMATODE PARASITES OF BIRDS 

 HETERAKIS TENUICAUDA Linstow, 1883 



73 



Hosts. — Caccdbis petrosa and Perdix graeca. 



Location. — Intestine. 



MorpJtology. — HeteraJcis (p. 50) : Head rounded, with 3 slightly 

 projecting lips. Esophagus 1/10 or 1/8 of total length. Lateral alae 

 present, extending to caudal region in both sexes. 



Male 22 mm. long by 1 mm. wide, according to Linstow, or 17.8 

 mm. long by 552/* wide, according to Seurat. Tail length given as 

 1/61 and 1/42 of total length by the two authors respectively, with 

 a fine sharply pointed appendage 215/* long. Preanal sucker 290/* 

 in diameter, located 450/* anterior to the cloacal aperture in Seurat -'s 



Figs. 99-101. — 99, Heterakis skrjabi.m. Male tail. After Skrjabin, 1916. 100. 

 heterakis tenuicauda. male tail. after llnstow, 1883. 101, male tail. after 

 Secrat, 1918 



specimen; its cutinous (chitinous) rim 50/* wide. Twelve pairs of 

 caudal papillae, according to Linstow (fig. 100) ; Seurat describes 

 only 12 but his figure (fig. 101) shows 13, there being an additional 

 pair at the sides of the sucker. The most anterior pair very small. 

 at level of origin of caudal alae (thus considerably anterior to 

 sucker). Spicules very wide, 980 and 9G0/* long, according to Lin- 

 stow, or 890/* according to Seurat. 



Female 14 mm. long by G00/* wide, according to Linstow (this 

 being surprising as it is much smaller than the length given by him 

 for the male) or 19.5 mm. long by GT2/* wide according to Seurat. 

 Tail awl-shaped, 1/13 to 1/11 of body length. Vulva 10.1 mm. from 



