NEMATODE PARASITES OF BIRDS 



365 



with small chitinous spines, posteriorly directed, arranged in trans- 

 verse rows. Posterior extremity obtusely rounded. Esophagus 1/3 

 the total body length, its anterior part cylindrical, posterior part 

 bulbous. Around the anterior part of esophagus 4 cylindrical cervi- 

 cal glands. Intestine large, cylindrical, ending at anus at posterior 

 extremity of body. 



Life history. — Unknown. 



Distribution, — Asia (Russian Turkestan). 



GNATHOSTOMA PELECANI (Chatin, 1S74) Skrjabin, 1916b 



Synonym, — Sclerostoma pelecani Chatin, 1874. 

 Host, — Pelecanus onocrotalus. The parasite is probably aberrant 

 so that this does not represent either primary or secondary host. 



M00^r^?-- 



Figs. 42. r >-42f>. — 425, Gnathostoma accipitri. a, General appearance : 6, hooks 

 of cephalic REGION. After Skrjabin, 1916. 426, Gnathostoma pelecani. a, 

 General appearance ; h, glandular apparatus ; c. vulva. After Chatin, 1874 



Location, — As larvae in cysts in the subcutaneous connective tissue 

 and as immature adults in cysts in the respiratory sacs. 



Morphology. — Gnathostoma (p. 3G4) : Length 3 to 4 mm. long. 

 Denticulations very pronounced in the anterior region of the body. 

 Head (fig. 426«) rounded, flattened, with 4 concentric and super- 

 posed series of chitinous hooks. Glandular apparatus (fig. 42GZ>) 

 in conjunction with the mouth consists of 3 pairs of tubes, 40^ in 

 diameter, of unequal length, the largest ones being external, the 

 others internal. Digestive tract consists of esophagus and intestine; 

 esophagus swollen posteriorly, its length equal to almost 1/2 that 

 of the body. Anus at posterior extremity of body, which ends in a 

 small mucronate point 7(V long. The immature adults showed a 

 characteristic vulva (fig. 42G c) in the median region of the body. 



Life history. — Unknown. 



Distribution. — Europe (France (Paris Museum)). 



