A biological study of Durvillaea antarctica (Chamisso) Hariot and D ...

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D. ha:rveyi are within the size range of New Zealand D. antarctica.
Morphological features Hooker' used to define D. haY'Veyi,
particularly the solid lamina, were applied to D. caepestipes (Mont.)
Skottsbg. by many botanists. Lindauer et aL (1961) pointed out tllat
there were differences bet\IIeen Hooker's and Montagne;s diagnoses;
the main difference being between their descriptions of holdfasts.
Montagne I s illustration of L. caepaestipes is. hO~lIeve:c > very similar
illustrated by Hooker in 1847.
Hooker collected several speci:(\1ens from the Cape Hotn region
which he identified as D. utiZis Bory. Longitudinal sections
through the laminae of two of these specimens 1 (Fig. 3.2d) \"ere compared
with similar sections through two D. haY'veyi specimens; the
lectotype, and the TCD specimen.
Cross sections through the laminae of these four specimens were
very simi lar (Fig. 3. 3), and closely re sembled drawings of c:t:"os s
sections of New Zealand D. antarctica in Herriott (1923) and Naylor
(1949, 1953a).
In the D. harveyi lectotype and both D. utilis specimens the mid
cortical region consisted of a narrow zOl1e of loosely packed star-­
shaped protoplas ts wi th thick ge latinous "JaIls (Fig. 3. 4e); while
the inner corte)~ was more loosely packed and contained some inter~
weaving hyphae z'unning longitudinally (a-a direction in Fig. 3.10)
l
and less commonly horizontally (b-b ) and vertically (c-c ). Walls
1 1
of both inner cortical cells and hypha.e \verethick and swelled to
form a gelatinous matrix if rehydrated. The width of the medulla
varied cons iderably in these three specimens, but its composj. tion
was the same: a central region of much branched and loosely inter-
1/1eaving hyphae separating the medulla into hllo plates of hyphae
running predominantly longitudinally and hor iZOi1 tally (Fig. 3. 4b ,d) .
The two pia te 5 were not a lvlays til e same width, ODe Bid",
being only half the width of the other. Small vaclJole-like spaces
oCCurred throughout the medulla (Pig. 3.4a,c).
The D. haY'veyi isotype from TCD differed from the ot.her three
specirnens by having relatively few interweaVing hyphae inth.e iOl1er
1. 13M specimen annotated "Durvillea ut1:Zi.s Eory, Hermit Island, Cape
Horn, l'.ntarct. Expo 1839-18