Figure 10 in Environmental control versus phylogenic fingerprint in ontogeny: The example of the development of the stalk in the genus Guillecrinus (stalked crinoids, Echinodermata)

Figure 10. Distal columnals of the adult specimens of Guillecrinus neocaledonicus. (a–f) Increasingly distal columnals with an increasingly early development of subsidiary crests: (a–d) facets with a pentaradiate symmetry; (e) facet with a four-part symmetry inherited from a juvenile stage similar to that of Figure 5d; (f) facet with bilateral symmetry and with two generations of subsidiary crests, inherited from a juvenile stage similar to that of Figure 5f, note the growth in diameter of the axial canal resulting from resorption of the perilumen stereom of the initial fulcral ridge. Scale bars: 1 mm.