Dawsonia

Dawsonia is the scientific name of several genera of organisms and may refer to:

References

Dawsonia (plant)

Dawsonia is a genus of acrocarpous mosses. Dawsonia, along with other members of the order Polytrichales, are taller than most mosses and have thicker leaves. Their sporophytes have conducting systems analogous to those of vascular plants. Dawsonia superba is found in New Zealand, Australia and New Guinea.Dawsonia longifolia is found in the Philippines, Indonesia, Malaysia, and Australia.Dawsonia superba and Dawsonia longifolia may be the same species.

Etymology

Dawsonia was named in honor of Dawson Turner (1775–1858), distinguished cryptogamist and friend of Robert Brown.

Height

Moss gametophytes lack internal transport tissues, which, coupled with the absence of cuticles, leads to the water-loss characteristic of bryophytes. As bryophytes can only grow when hydrated, the lack of conducting tissue restricts most mosses, even in relatively wet habitats, to a low stature.

However, Dawsonia (along with other genera in the Polytrichales order) reaches heights comparable to those of vascular plants. Polytrichales are acrocarpous mosses – they have vertical stems with terminal reproductive structures, with the sporophyte growing vertically (along the same axis as the gametophyte stem).

Dawsonia campanulata

'Dawsonia' campanulata is an organic-walled Palaeozoic organism of unknown affinity . It resembles a shell or purse.

References