Internal Parasites 143 



in large numbers, they sometimes become rolled and matted 

 into a ball which may cause complete stoppage of the in- 

 testine. 



The round worms are white in color and vary in length 

 from J inch to 5 inches. The head end is sharp pointed, 

 while the tail end is more blunt. Round worms are seldom 

 passed in the feces unless present in very large numbers. 

 When a worm is passed it soon dies in the droppings or is 

 eaten by another fowl. 



Dispharagus spiralis, a small worm about \ inch in 

 length, is often found in the esophagus and occasionally in 

 the crop or intestine. 



Dispharagus nasutus, about | inch long, occurs in the walls 

 of the gizzard of fowls. It sometimes becomes so numerous 

 as to cause serious loss. 



Another nematode, Cheilosperura hamulosa, parasite in 

 the gizzard of the chicken has recently been recorded in this 

 country by Ransom.^ Specimens have been found from the 

 District of Columbia as far west as Kansas. 



Two other nematodes, Trichosoma strunosum and Gingy- 

 lonema ingluvicola, have been found in the pharynx and 

 esophagus of chickens.^ 



Heterakis perspicillum, from 1| to 3 inches long, is very 

 common in the intestines of fowls. They sometimes become 

 very numerous and may become rolled into rather large 

 balls which obstruct the passage of the food. 



Scott ^ has found that this nematode may be transmitted 

 to young chicks through an earthworm (probably Helodrilas 



" Ransom, B. H., "The Occurrence of Cheilosperura hamulosa 

 in the United States." Science, N. S., Vol. 35, p. 555, 1912. 



^ Crurea, J., Zeitschr. Infekt. u. Hyg. d. Haust. Bd. 15, pp. 49-60, 

 1914. 



' Scott, J. W., "A New Means of Transmitting the Fowl Nema- 

 tode, Heterakis perspicillum." Science, N. S., Vol. 38, pp. 672-673, 

 1913. 



