Siegenian

The Siegenian was an epoch of the Devonian period spanning from 411.2 +/- 2.8 To 407 +/- 2.8 Ma. The term overlaps with parts of the internationally recognised Pragian and Emsian epochs, and although once widely used[1] is now deprecated.

References

  1. ↑ Niklas, K.J. (1985). "The evolution of tracheid diameter in early vascular plants and its implications on the hydraulic conductance of the primary xylem strand". Evolution (Society for the Study of Evolution) 39 (5): 1110–1122. doi:10.2307/2408738. JSTOR 2408738.