Die Embryonalentwicklung der Paradiesschnecke ... - TOBIAS-lib

Kapitel 2
Fig. 3: M. cornuarietis, 4- and 4.5-day-old embryos; A: control embryo in Stage IX, 4-
day old, left lateral view; B: histological horizontal section of a control embryo, 4-day
old, plane of section indicated by dashed line in sketch (left lateral view), HE-staining; C:
Pt-exposed embryo, 4-day old, left lateral view (from Osterauer et al., Evol Dev, 2010,
12, 474–443, c○Wiley-Blackwell, reproduced by permission); and D: histological horizontal
section of a Pt-exposed embryo, 4.5-day old, plane of section indicated by dashed line in
sketch (left lateral view), HE-staining. an, anus; anp, anal cell-plate; f, foot; h, head;
i, intestine; ls, larval stomach; m, mouth; mtc, mantle cavity; mte, mantle edge; oe,
oesophagus; ps, peristome; sh, shell; shg, shell gland; shgr, rudimentary shell gland; tn;
tentacle; vs, visceral sac. [Color figure can be viewed in the online issue, which is available
at wileyonlinelibrary.com.]
exposure), it is obvious that a horizontal rotation of the visceral sac relative
to head and foot does not take place in the platinum group. This can also be
seen in Figure 4C,D. Figure 4C shows a transverse section through a control
embryo. The mantle anlage (under the shell) has spread across the visceral
sac, which leads to a rotation of the visceral sac while forming the outer
epithelium of the mantle. During this process, the mantle cavity develops.
In contrast, the embryo from the platinum group (Fig. 4D) neither develops
a mantle cavity nor a mantle itself. The mantle anlage has stopped growing,
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