104 
PROF. DAMMANN 
remained isolated ever since, being taken out only when portions of 
flesh were wanted for examination. No subsequent feeding with trichi- 
niae occurred, and an accidental infection by rats could be, with tolera¬ 
ble certainty, excluded. Rats were never seen in the stall, which has 
an asphalt floor and well plastered walls ; the presence of cats kept 
them at a distance ; moreover, the author had never found trichiniae in 
a large number of rats examined. 
On the 3d of February, 1875, and the 12th of February, 1876, por¬ 
tions of muscle were excised from the region of the shoulder, and on 
both occasions microscopical examination showed the presence of encap- 
suled trichiniae. Rupturing a capsule with a needle gave exit to a worm, 
which, on slightly warming the slide, executed lively movements. Por¬ 
tions of the muscle last excised were administered to two rabbits, one 
of which already had old trichiniae in its muscles. Eighteen days after, 
the muscles of both animals were crowded with young, recently-migrated 
parasites. i hus the trichiniae in this pig had, for somewhat over 11 
years, letained their vitality and power of development, and the suppo¬ 
sition regarding the length of life in encapsuled worms is, by this exper¬ 
iment, satisfactorily confirmed. 
A point of some interest is that in spite of the lengthened sojourn 
of the worms in the muscles, they were not surrounded by true calcar¬ 
eous sheaths, but possessed somewhat opaque capsules, scattered over 
with dark gianules, through which the outlines and general structure of 
the woims could be plainly seen. Complete calcification of trichiniae 
capsules has not yet been found in pigs, which was believed to depend 
upon the fact that the animals were killed before the process super¬ 
vened. Several years, at least, are required, but in this instance 11 did 
not suffice. The food of the animal consisted chiefly of peas and pota¬ 
toes. The author raises the question whether it is not a peculiarity in 
the pig that entire calcification of the capsules does not, as a rule, 
occur. Measurements proved that no appreciable change in the density 
of the capsules had taken place in the year between the two last 
excisions. (Deutsch Zeitschr.f. Thiermcdicin, Bd. Ill, lifts. 1 and 2.) 
