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for fowls than earthworms. Chicks two days old eat them 

 greedily. 



Finally, it cannot be denied but that we have effectually disproved 

 Dr. Megnin's conclusion that no other animated medium except 

 the birds themselves has any share in spreading the disease. 

 We will recapitulate the several points we consider established 

 by this investigation. 



First, That the earthworm is the original host of Syngamus 

 trachealis is proved by eight separate successful experiments, in 

 feeding them to chicks. None of the chicks fed earthworms 

 from the infected spot failed to have the gapes in seven days. 

 That all earthworms do not contain the embryos of Syngamus, 

 proved by feeding three chicks earthworms from a place where 

 no gapes existed. They failed to have the gapes. That the 

 robin {Turdus migratorious) i may act as a host for Syngamus, 

 and thus be instrumental in spreading the disease, is proved by 

 feeding three robins and finding full grown worms in their tra- 

 cheas. That the earthworm is only a bearer, or means of con- 

 veying the embryo to the fowl, is proved by feeding the embryos 

 hatched from the eggs to a chick and thus producing the gapes. 

 That they pass through the oesophagus is demonstrated by find- 

 ing them beneath its mucous membrane, and also in the act of 

 passing through into the lungs. The embryo of Syngamus in 

 the earthworm has been identified by tracing it through its differ- 

 ent stages, from the earthworm to the trachea of the chick, and 

 also by artificial culture. That the embryo of Syngamus in the 

 earthworm is but slightly affected by the anthelmintics which 

 have been used to prevent and cure the disease, as asafoetida 

 and garlic. They cannot be relied on for this purpose. Lastly, 

 anv locality where the gapes prevails can be rendered safe for 

 fowls by destroying the infected earthworms in the ground with 

 common salt. 



The life history of Syngamus trachealis is as follows: Earth- 

 worms containing the embryos are eaten by the fowl. The em- 

 bryos are liberated from the intestine of the earthworm and 

 work their way through the oesophagus into the lungs and 



