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POPULAR SCIENCE REVIEW. 
canal of their host, though the females are distinguishable 
from the males even in the capsule. 
Without entering into further details as to the worm, it is 
important to notice the capsule which surrounds it, and which 
consists of the thickened sarcolemma, and a special envelope 
for the parasite within this. Leuckart has demonstrated that 
the trichinae lead to the removal of the muscular tissue, and 
are really living in the muscular fibre itself. They are there- 
fore not, as some persons have supposed, in the areolar tissue 
between the muscular fibres ; and the fact of their existence 
in great numbers, occupying the place of the active muscular 
element, explains symptoms observed in marked cases of 
trichinous disease. 
From a report in a German veterinary periodical, to the 
effect that trichinae could live in roots, and that the domestic 
quadrupeds derived them from rotten turnips, which abound in 
trichinae, I have taken some pains to ascertain if any truth 
existed in such statements. I find that a species of anguillula 
preys on the turnip, and is found coiled up in cells much like 
the trichina ; but it is altogether a different parasite ; and having 
fed two pigs on such turnips, I obtained negative results. 
At one time it was supposed that trichinae, as found 
in the muscles, were the larva© of a tricocephalus ; but 
the experiments of Virchow, Leuckart, and others, show that 
the fully developed trichina is a distinct filiform worm, occu- 
pying the alimentary canal, and giving birth to young trichina©, 
which pierce the walls of the intestine, and on reaching the 
muscles become capsulated. The appearance of the muscle is 
well shown by the specimen drawn in the annexed plate ; and 
as the recognition of the disease in the lower animals is the 
best means to prevent the malady spreading to man, I may 
now refer to the symptoms manifested by pigs, dogs, cats, 
rabbits, and other quadrupeds. 
The symptoms have been ascertained in the course of expe- 
riments, and they are found to vary somewhat in different 
cases. Not uncommonly rabbits, which are made to swallow 
thousands of trichinae, appear to suffer no indisposition for 
some days, and then die suddenly. Leuckart fed nine rabbits 
with half an ounce of muscle, containing about 160,000 trichinae, 
and repeated the dose about three days afterwards. No 
symptoms of importance resulted until the seventh day after 
the first administration, when one of the rabbits died. After 
death, the diaphragm and the serous coat of the intestine were 
of an intensely red colour. Exudations had occurred from the 
mucous membrane, on which numberless trichina© with their 
embryos were found. Leuckart and Claus then traced the 
embryos on the peritoneal coat, having therefore forced 
through the intestine, and many were also found in the 
