Mindeskrift i anledning af hundredaaret for Japetus Steenstrups fødsel / XXV. Contributions to the Biology and Morphology of Spiroptera (Congylonema) Neoplastica N. Sp. / 25 (1914) Author: Hector Jungersen, Eugen Warming Table of Contents / Innehåll | << Previous | Next >>
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The shape of the capsule is somewhat differing according to the various individuals;
most probably this is proportionate partly with the space which is left to the disposal
of the worm during the aet of encysting, partly with the state of contraction of the
surroimding muscles. The circumference generally is nearly circular and somewhat flat-
tened, the capsule being thus lenticular and thickest in the middle. Often, however,
it has a more or less longish shape almost as a somewhat flattened egg.

As a rule the worm if not disturbed will keep rather quiet withiri its capsule,
small slidiiig movements being observed as the spiral is contracted or relaxed; greater
movements no more than changing of place will occur.

When isolated from the surrounding muscular tissue and placed under a cover-
slip in a solution of physiological common salt the larva within its capsule will
show itself most extraordinarily animated, owing to the unusual conditions. It
moves about inside the capsule in a most energetic way, describing with its body now a
spiral, now a figure of eight, the head sometimes in the centre of the capsule, some-
times in the periphery.

Fig. 3.

Under the microscope the isolated capsule presents itself very thick-walled, com-
posed of a thick granular mass the consistence of which is similar to that of a thick
protoplasm. A membrane of connective tissue will generally not be found. The
capsule probably consists of degenerated muscular tissue from the surrounding muscles.
After a while the movements of the larva grow more animated; it begins trying to
break through its capsule, now and then putting its head into the wall of the capsule
which very easily yields to the pressure. As the worm draws back into the cavity a
canal is left which will contract but very slowly. By
and by several bored passages may be found in the
wall, reaching more or less deep into it and often
wound according to the direction of the worm. Finally
it may happen that the worm gets quite through the
wall and escapes. This faet has been dwelt on at
some length as it seems to throw light upon the pe-
culiar consistency of the capsule. Most likely the un-
usual toughness, which is evidently characteristic of it,
will be of great consequence to the larva, sheltering it
from the pressure of the surrounding muscles during
their contraction. The text-figure 3 shows such a capsule and its cavity which has
harboured the larva, as well as the bored canal through which it has escaped; also
some other canals half contracted appear distinetly.

The encysted larva measures about 1 mm. in length, most frequently somewhat
less, varying conspieuously in size; the smallest one found had a length of 792 μ,

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