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

54
several narrow whip-like thongs. The absence of any stipe or
holdfast, and the fact that Lima is mentioned (when Lima is far
north of the northern limit of D. anta:r'ctica in Chile) suggests
that it was a drifting specbnen.
LamouroWl: mistakenly believed that it wo"s the same as Le
Gentile's "porra". No valid description of Laminaria porroidea was
ever published.
3.6 CONCLUSIONS
I :cecognise four species of Duroi llaea: D< potatorum
(Labillardiere) Areschoug, D. antarctica (Chamisso) Hariot, D,
willana Lindauer and a new species D. chathamica. Of eight
other validly published species, one (D. simplex Suhr) is a
misidentification of a North Atlantic laminarian; the other seven
are synonyms of D. antarctica. There is insufficient evidence to
retain either D. aaepeatipes (Montagne) Skottsberg I or D. hOY'veyi
Hook.fil. as separate entities, because type material of both species
is inseparable from D. antarctica.
Most of the taxonomic and nomenclatural confusion has arisen
when botanists described new species from young plants or fragments
of solitary plants without being fully aware of the morphological
plasticity of DurvilZaea species.
ADDENDUM
Since this chapter ~·Jas typed I have obtained infopnation from
the Botanisches Institut und Botanischer Garten der Universi"tat at
Kiel. There is type ma'terial of Halymenia inaurvata and Dux'viUea
mastix in Suhr's herbarium. All specimens wCY.'e collected at Valparaiso,
the type locality of both species. There are three specimens
annotated Halymenia incuY'Vata Suhr, two being attached to the srune
sheet. The solitary specimen (also annotated Du~viZZaea utilis Bory)
is without i"ts holdfast. Details on the ba.ck of the sheet state
-that it was collected in March 1836. The laxger of the other.: tHO
specimens (collected 1837}is without both stipe and hold fast , The
smaller (R), which I regard the holcitype, is complete and closely
resembles Suhr's 1839 illustration of the species. Attached -to em
adjoining sheet are two copies of Suhr's illustration and his handwritten
description.
The D. mastix material (on two sheets) is in ct file -togei:her
with an adjoining sheet bearing the label, a copy of Sunr's 1841
illustration and matching rough sketches. The file is labelled "D,
utilis Bory/D. mastix Suhr/ex Herb. Suhr/Vi::\lparaiso". It consists
of a large piece of honeycollibed blade (identical to one of the 'major
divisions of the D" mastix specimen illustrat8d) aod several nan::m'l
honeycombed thongs" Ii:. matches the iso"type material at Lund, and is
undoubted ly holotype material.