l62 



THE ANIMAL PARASITES OF MAN 



Okayama, Kumamoto, Nagano and Tokushima are the principal centres. 

 [Stiles has also observed this species in North America, and Naunyn saw 

 a case in Strasburg in a colonist who had lived in Mexico and California 

 for fifteen years (Deutsch. Med. Woch., 1897, Vereins Beil., No. 20, p. 146). 

 F. V. T.] 



In addition to its occurrence in the royal tiger and in man, Parago- 

 nimus westermani, according to Janson, has been found in pigs ; according 

 to Railliet and Katsurada in the dogs of Japan, and according to Ward 

 and Stiles it also occurs in dogs, cats and pigs in N. America. 



FIG. 94. Egg 'of 

 Paragonimus westermani 

 (Kerb.), from the spu- 



The presence of flukes in the lung is naturally not innocuous 

 to man, but the symptoms are, as a rule, so trifling that the 



patients are able to follow their occupations 

 and hardly ever consult a doctor concerning 

 the haemoptysis. The worms are found, in 

 the case of human beings, often singly, in 

 cysts with hard walls the size of hazel nuts, 

 that do not belong to the actual tissue of 

 the lung, but to the bronchial tubes with 

 which they communicate. 



[This disease occurs principally in the 

 male sex, but seldom in old men ; children 

 and women are seldom affected. The man- 

 ner of infection is unknown. F. V. T.] 



One danger threatens the patients, in so 



far as [i is P ssible for lar e blood-vessels 

 to be opened by the disintegration of the 



lung tissue in the vicinity of the cysts, and thus copious haemor- 

 rhage may be set up. Moreover, the flukes also appear to enter 

 the blood-vessels and then are carried about in the body; at all 

 events softened centres or tubercle-like neoplasms have sometimes 

 been found in the brain or other organs, and have been found to 

 contain the eggs of the lung fluke in large numbers. In this posi- 

 tion the worms appear to have perished at some period before the 

 examination, but it is certainly not improbable also that the eggs 

 invade the circulation direct from the lung, and are then conveyed 

 to different parts of the body. 



[Kanamori doubts that the ova found by Yamagiva and others 

 in the brain, liver, &c., have anything to do with this parasite, 

 especially as they exhibited no lid, and believes they belong to 

 another parasite. He found them in a cirrhotic liver and in an 

 adenoma_pf the rectum. F. V. T.] 



As to the development, only the following details are known : 



