(ESOPHA GOSTOM UM 



661 



(Esophagostomum Molin, 1861. 



Strongylidse in which the mouth is small and circular, with a 

 chitinous ring, which carries a fold and six papillae. There is a 

 marked swelling just behind the anterior extremity. Male bursa 

 with two equal spicules; female with two ovaries, and the vulva 

 opening situate near the anus. 



Type Species. — (E. subulatum Molin, 1861 ; (E. dentatum (Rudolphi, 

 1803). 



S^Bcies.— (Esophagostomum apiostomum and CE. stephanostomum , 

 var. thomasi Railliet and Henry, 1909, are known in man, but other 

 species are found in the gorilla, chimpanzee, and other monkeys. 



(Esophagostomum apiostomum Willach. 



Synonym. — CEsophagostomum brumpti Railliet and Henry, 1905. 



This worm was found by Brumpt in cyst-like nodules in the caecum 

 and colon of a negro on the Omo River, near Rudolph's Sea in East 

 Africa. Found also in monkeys. 



According to Leiper, this parasite occurs in 5 per cent, of the 

 natives of Northern Nigeria. 



Morphology. — -Female 8-5 to 10*2 millimetres long by 0*295 to 0-325 milli- 

 metre broad, white and cylindrical, tapering towards the posterior end. 

 Cuticle transversely striated. There is a distension behind the oral cavity 

 which is formed of a cuticular band with a crown with twelve spines ; on the 

 front and inner side lamellae; six head papillae (two lateral, four submedian). 

 Posterior end rounded off with three broad undulations. 



Life-History. — Outside the body similar to that of the Anky- 

 lostomes. 



Pathogenicity. — ^The young form cyst-like nodules in the large 

 intestine. 



(Esophagostomum stephanostomum var. thomasi Railhet and 



Henry, 1909. 



This species was found by Wolferston Thomas in tumours, 

 numbering 187, in the large and small intestines of a man in Brazil. 

 The tumours were in some instances large enough to diminish the 

 lumen of the bowel. Each tumour contained a male and a female 

 worm. The species (E. stephanostomum Stossich, 1904, was found 

 in the large intestine of the gorilla, and a variety GE. stephanostomum 

 var. dentigera Railliet and Henry, 1909, is found in the chimpanzee. 



Morphology. — 'Body cylindrical, thick, only attenuated towards the ex- 

 tremities. Buccal capsule with an external crown of 38 lamellae. Male 

 17 to 22 millimetres in length and 0'75 millimetre broad. Bursa thick at 

 the sides, with one spicule i*38 to i'475 millimetres long. Female 16 to 20 

 millimetres long by 0-9 millimetre broad. Vulva in front of the anus, 0-5 to 

 0*525 millimetre from the posterior end. 



Life-History.— Not known. 



Pathogenicity. — Forms tumours in the wall of the small and 

 large intestines. 



