PARASITOLOGY. 



143 



greenish, cheesy pus has accumulated around it ; in 

 nodules larger than a pin-head the entire contents 

 are a cheesy mass ; the cyst wall is ruptured and the 

 worm is found free, wandering within the capsule ; 

 in the larger nodules the cheesy material is quite 

 hard except at the side where the worm is found. 

 Nearing maturity the worm leaves the nodule and 

 becomes sexually mature only in the intestinal tract; 

 the nodule now gradually shrinks in size until it is 

 quite small and filled with earthy material. 

 Animals l7ifested—T\iQ sheep, goat and ox. 



rig. 5 3— Nodular Disease. 



a, Nodule caused by larva of Oesophatjostome of Columbia. 



b, Section of small Intestine. 



Parts Lifested.—^moW and large intestines. 



Disease Produced.— ^o&a\2iV disease. 



Condition Produced.— ^o^\x\dCC disease is common 

 in native but seldom if ever found in range sheep. 

 In badly infested cases the entire intestinal canal 

 may be thorougly studded with the nodules, which 

 are irregular in outline and push the serous coat out; 

 the nodule lies under the serous covering of the 

 bowel and can be readily told from the tubercle pro- 

 duced by the bacillus of tuberculosis by the fact that 

 the latter is smooth, and that in tuberculosis the 

 lymph glands adjacent to the affected part will be 



