NEMATODE PARASITES OF BIRDS 



35 



Pyrrocorax alpimts, Strix noctua, Sturnus vulgaris, Tetrao urog al- 

 ius, "thrush." Chapin notes that the specimens from birds other 

 than the Galliformes need further study; those from Corvus, spp. 

 may be S. gracilis. 



Location. — In the trachea and bronchi as adults; in the lungs as 

 larvae; immature worms have been found in the peritracheal tissue 

 and air sacs (Megnin). 



Morphology. — Syngamus (p. 34) : Cylindrical red worms, the 

 color more pronounced in the female. Head (fig. 37) enlarged and 



Fig. 36. — Stngamds trachea. Outline. After Chapin, 1025 



truncated. Mouth orbicular, with a hemispherical chitinous capsule, 

 at the base of which are usually 8, occasionally 9, sharp teeth; the 

 mouth is surrounded by a chitinous plate, the outer margin of which 

 is incised to form 6 festoons opposite each other, with 4 smaller fes- 

 toons between them in opposed pairs; a lateral papilla is between 

 each pair of small festoons, and 4 submedian papillae are present, 1 

 at each end of the large festoons. The male is permanently at- 

 tached in copula to the female, forming a Y (fig. 36). 



FlG. P»7. — SYNGAM0S TRACHEA, HEAD. (I. TKETII IN 8-TOOTHED (NORMAL) FORM \ 

 b, FRONT VIEW OF HEAD; c, TEETH IN 9-TOOTHEI> FORM. AFTER CHAPIN, 1925 



Male 2 to mm. long by 20G> wide. The bursa (fig. 39) is ob- 

 liquely truncated, provided with rays somewhat similar to those of 

 C. bronchialis (p. 42), sometimes with strikingly asymmetrical dor- 

 sal rays. The male is permanently attached to the female about the 

 vulva. Two equal, slender, short spicules (fig. 38), 57 to G4/x long 

 according to Chapin, who states that the reports of 140/x spicules in 

 this species probably refer to another species. 



Female 5 to 20 mm. long (longer in the turkey) by 350/* wide, 

 somewhat more slender anteriorly and irregularly swollen when 



