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further proof on this point, for Dr. Megnin himself abandons 

 the theory. He says, in a supplement to his essay, written 

 about twenty months after it (see Report of U. S. Department 

 of Agriculture, 1884, page 283) : "We pointed out that the eggs 

 ejected during the coughing fits hatch in water, and that the 

 embryo resembling anguillula may live in this medium for 

 many months, because we have kept some alive almost a year in 

 a low temperature. The birds are infected by drinking the 

 water containing these embryos." He also denies that any other 

 animated medium, except the birds themselves, has any share in 

 spreading the disease (see same Report, page 280). That the 

 gapes can be artificially produced by feeding the embryos of 

 Syngamus hatched in water to chicks, we readily admit, for we 

 have proved such is the case by experiment 13. But we deny 

 that this is the natural way in which they contract the disease. 

 To prove the correctness of our conclusions, we have eight 

 carefully conducted experiments with chicks by feeding them 

 earthworms from an infected spot, in which every other mode 

 of taking in the embryos was excluded, the gapes being inva- 

 riably produced in each case. Now, if this is not the natural 

 way, then the earthworm must be an accidental host. That 

 such is not the case we consider proved by finding the embryos 

 of Syngamus living in the earthworm at all times of the year, 

 winter as well as summer. They have been found in nearly all 

 the earthworms of an infected spot one year after any cases of 

 the disease in the immediate vicinity. We have found twenty 

 of these embryos in a single earthworm, and often five to ten. 

 It makes no difference whether the embryo is taken in water 

 which the bird drinks, or in the intestine of the earthworm; the 

 effect is the same. Furthermore, it is also in accord with the 

 habits of many worm parasites that a bearer aids them in ob- 

 taining access to their final host, and the greater number of 

 Nemetoid worms, to which class Syngamus belongs, are directly 

 developed from their embryos without any metamorphosis 

 necessitating a change of hosts, in which respect they are un- 

 like the Fluke and Tape worms. There is no food more natural 



