72 BOARD OF AGRICULTURE. 
the human intestine, or there may be several together, the 
number depending only upon the number of living young | 
swallowed. 
It is, therefore, obvious that this tape-worm can be acquired 
only by eating raw or undér-done pork. In this country the 
principal kinds of food serving as sources of this tape-worm 
are raw smoked ham and raw sausages, but soldiers and others 
are often obliged to eat their pork-rations uncooked, and thus 
obtain the parasites. Our recent war was the means of greatly 
increasing the numbers of this and other parasites, both in- 
ternal and external. 
Persons harboring the mature tape-worms become in their 
turn the means of diffusing the race. Each mature joint cast 
off contains several thousands of eggs, each of which encloses 
an embryo, nearly ready to hatch, and as these joints are con- 
tinually being discharged during the whole life of the worm, 
which may be ten or twelve years, it is evident that one per- 
son may thus be the means of diffusing many millions of eggs, 
most of which will no doubt perish, but the chances are good 
that some of them will find their way into the stomachs of 
hogs, either with their food or in water. 
The free joints or proglottides have an independent life for 
a few days and are capable of moving and crawling about to 
a considerable extent. In a short time, however, the myriads 
of embryos in the interior so increase in size that the walls of 
the proglottis burst open and thus liberate the eggs. The 
eggs are globular and very small, their average diameter 
being about s$z of an inch; the shell is comparatively 
thick, being z¢5y of aninch. They are so small that they 
may be blown about by the winds, carried on the feet of in- 
sects, or may be suspended in unfiltered waters. They may, 
therefore, also readily adhere to lettuce, celery, and other 
garden plants, or to fallen fruit, especially when night-soil is 
used as manure, and unless such food be carefully and 
thoroughly washed, there is always more or less danger of 
eating the eggs of this and other parasites. When these eggs 
are swallowed, either by hogs or human beings, they hatch as 
soon as acted upon by the gastric juice, and disclose their con-° 
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