NEMATODE PARASITES OF BIRDS 



239 



Hosts. — Primary : Gallus gallas, Bonasa umbellus, Gaccabis petrosa, 

 Columbia. livia\ Mdeagris gailopavo, Phasia/rms gallus, Numida me- 

 leagris, Quiscalus quiscfula; secondary: .^owbug (Porcellio laevis). 



Location. — Esophagus, proventriculus, and intestine, fixed in 

 mucosa as adults, and encysted in connective tissue about esophagus, 

 crop, proventriculus and intestine and in the mesentery of primary 

 host; in anterior portion of digestive canal of secondary host. 



Morphology. — Dhphmynx (p. 237) : No vesicular swelling ante- 

 riorly. Four wavy cutaneous cordons (figs. 301, 302, and 303a) on 

 anterior end, originating at the 2 papilliform lips, not anastomosing, 

 but recurrent, the distal extremity of the cordons turning forward 

 and extending anteriorly a short distance. Postcervical papillae 

 small, bicuspid, situated between the recurrent branches of the cor- 

 dons. Body usually rolled in a spiral. 



Fig. 301. — Dispharynx spiralis. Male. After Piana, 1897 



Male 7 to 8.3 mm. long by 230 to 315/x wide (fig. 301). Cordons 

 415 to 515/i long. Five pairs of postanal and 4 pairs of preanal 

 papillae. Cloacal aperture about 275/* from tail end. Long spicule 

 400/t long, slender and curved; short spicule 150/* long, navicular. 

 Ventral surface of body in cloacal region and for a certain distance 

 anterior to cloaca covered with small, elongated shields which give 

 the appearance of a longitudinal striation. 



Female 9 to 10.2 mm. long by 360 to 565/* wide (fig. 302) . Cordons 

 900/* to 1.06 mm. long. Anus 120/* from tip of tail. Small mucron 

 on tip of tail. Vulva in posterior portion of body, 2 to 2.45 mm. 

 from tip of tail. Cylindrical ovejector (fig. 3035) curved, S-shaped 

 at its origin, and then directed anteriorly; the limiting boundary of 

 the vestibule and sphincter is clearly marked by an annular cuti- 

 cular fold; varnish gland (trompc) unpaired, 250/* long. Eggs 36 

 to 40/t by 21/t, embryonal ed when oviposited. 



Life history. — According to Piana, the life history of what he 

 called Dispharagus nasutus, but which was apparently Disph/trynx 

 3012—27 17 



