THE TURKEY IMPORTANT IN THE SPREAD OF GAPEWORMS. 7 
harbored, respectively, 92, 75, and 36 pairs of gapeworms in their 
tracheas, the females ranging in size from 4 to 11 mm. Besides the 
worms in the trachea there were a few immature gapeworms in the 
lungs of each chicken. 
Some of the same culture was fed on February 7 to three turkeys 
nearly a year old. Nineteen days later one of the turkeys was 
observed to be sick and was killed. There were no gapeworms found 
in the lungs, but 483 pairs were present in the trachea, the females 
averaging 24 mm. in length. The feces of the two remaining turkeys 
were first examined 21 days after infection and at this time con- 
tained large numbers of gapeworm eggs. The birds were coughing 
and there was a brown crust on their bills, formed by the drying of 
expectorated mucus. On March 17, 38 days after infection, these 
two turkeys were still coughing, but the brown crust was no longer 
present on their bills. On April 14, 66 days after infection, gape- 
worm eggs were still present in the feces. April 29, one of the 
turkeys which had been ailing was killed, the lungs and one bronchus 
being found affected with a gangrenous necrosis. The trachea 
contained 22 pairs of gapeworms, the females averaging 33 mm. in 
length; also many broken pieces of dead worms were found. The 
third turkey was kept alive. December 16, 10 months after infection, 
an examination of the feces of this turkey failed to show gapeworm 
eggs. 
In this experiment adult turkeys (nearly a year old) and young 
chickens (8 weeks old) became heavily infested as the result of a 
single feeding with gapeworm material, while chickens approaching 
maturity (21 weeks old) that were fed repeatedly with gapeworm 
material (including material from the same culture as that fed to 
the turkeys and the young chickens) failed to become infested. Evi- 
dently, therefore, adult turkeys and young chickens are much alike 
in their susceptibility to gapeworm infection, and in this respect both 
are quite different from adult chickens or chickens approaching 
maturity. 
FACTORS IN THE SPREAD OF GAPEWORMS. 
From the results of the investigations briefly recorded above, it 
would seem that turkeys are an important factor in the spread of the 
gapeAvorm, and that adult chickens are relatively unimportant as 
carriers of the parasite. In the perpetuation of gapeworms from year 
to year on infested poultry farms the two chief factors appear to be 
turkeys and contaminated soil. Whether guinea fowls are like turke}^ 
in commonly harboring gapeworms throughout life or whether they 
are like chickens and tend to lose their susceptibility as they become 
mature is uncertain. Little is known also as to the relation of pea- 
fowls, ducks, geese, pigeons, and various wild birds to the spread of 
