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authors have observed splanchnopleural thickening in the segments
adjacent to the point of transection which could be concomitant with
the release of different types of wandering cells. Fig. 13 illustrates this
phenomenon in Nereis. In Fig. 13 (1) the thickening is localized in the
segment anterior to the healing zone; in Fig. 13 (2) the various types of
cells issuing from this proliferation are shown.
FIG. 13. Nereis diversicolor. 1. Appearance of régénérât ion bud 17 days after transection.
S, Splanchnopleural cells in multiplication in the segment anterior to transection. 2.
Aspect of the splanchnopleura (S). A, Amoebocyte; H, haemohistoblast ; L, lymphocyte;
Li, linocyte.
From all these observations it can be concluded that free coelomic
cells certainly participate to varying degrees in regenerative processes.
Observation of these cells, their origin, relationships and role should be
followed up, for example by examination of living cultures together
with electron microscopy.
The concept of the totipotency of the mesodermal cell, as held by
Dehorne and Stephan-Dubois for Nereis diversicolor, does not apply to