NEMATODE PARASITES OF BIRDS 



65 



Female 9 to 12 mm. long by 425 to 470/*, wide. Esophagus 1/8.4, 

 tail 1/7.3 of total body length; the tail ends in a very long slender 

 point as in the oxyurids. Vulva a little anterior to middle of body, 

 dividing the body in a ratio of 22 : 25 ; posterior to it a row of 2 to 3 

 papillae, and at times a papilla anterior to it. The number and posi- 

 tion of these vulvar " papillae " are not constant and Baylis and 

 Daubney (1922) suggest they are due to the action of the sucker of 

 the male in attempting copulation. Eggs 70 to 75/x long by 42 

 to 46/* wide. 



Life history. — Probably similar to that of H. gallinae (p. 54). 



/mm 



2/Wfl7 



Figs. 84-86. — 84, Heterakis hamulus. Male tail. After Linstow. 

 1906. 85-86, Heterakis interlabiata. 85. Anterior end; 86, male 

 tail. Aftejr Ortlepp, 1923 



Distribution. — Europe (Germany (Zoological Museum Koenigs- 

 berg), France, England), Asia (India), and North America (United 

 States and Canada). 



Wassink considers that the specimens described by Lucet and Henry 

 as II. isolonche are identical with his species, II. neoplastica (p. 65), 

 but the evidence which he presents, based mainly on the crossing of 

 the extruded spicules, is not conclusive. 



HETERAKIS NEOPLASTICA Wassink, 1917 



Hosts. — Phasianus colchicus, P. satscheunensis, Thaumalea obscurus, 

 and T. pictus. 



I ocation. — Ceca. 



Morphology. — Heterakis (p. 50) : Head with 3 hemispherical lips, 

 each lip bearing 2 short papillae. Esophagus cylindrical with pyri- 

 form bulb. Lateral alae narrow, extending almost the whole length 

 of the body (to origin of caudal alae in male). 



