The Botany of Iceland - 01.12.1928, Side 102

426
JOHS. BOYE PETERSEN
Brand has given very weighty reasons (1925, p. 324) for not fol-
lowing Wille in calling the present species by Agardh’s name Proto-
coccus viridis. There can he no doubt that the íirst to describe the
species so well that it was recognisable was Nágeli (1. c.). Hence it is
only fair that his specific name should he retained. As, however, the
species cannot well be classed in the same genus with Pleurococcus vul-
garis Men., I prefer to use the new generic name given it hy Brancl.
The species is uncommon in Iceland. It was found in 7 samples in
all, and I have nowhere seen such extensive growths as are common in
Denmark and other European countries. In Iceland it has been found
on woodwork, stones and rocks (400, 408) and in one sample originating
from turf at the base of a wall (40).
Pleurococcus vulgaris Menegh. Boye Petersen 1915, p. 319 Tab I,
fig. 2, 3.
N. Icel. 216 — N. W. Icel. 261 - S. Icel. 270, 275, 286, 292.
In the above-mentioned samples I have ascertained the presence of
a form which is quite in accord with the P. vulgaris mentioned by me
in 1915 (1. c.). By the aid of chlor-zinc-iodine I was able to demon-
strate pyrenoids in the cells, just as also the dimensions of these were
the same as I have stated. According to the data it is doubtful whether
this form is identical with the genuine P. vulgaris Men. (Monog. No-
stochinearum Torino 1843, p. 30 (cit. after Brand 1925)), and possibly
P. vulgaris Boye P. should be given a new name. It has been impossible
for me to decide this, since I have had no access either to Meneghini’s
original figures or to any orig'inal specimen. Borzi, however, saw an
original specimen (1895, p. 207), and ascertained that the chromatophore
contained a pyrenoid. Chodat used this to establish the diíference be-
tween P. vulgaris Men. and P. vulgaris Nág. (= P. Nðgelii Chod.) (Chodat
1897, p. 117, 1902, p. 279). Later (1909) Chodat formed the opinion
that P. vulgaris Men. was a developmental stage of a Prasiola, and Brand
thinks so too (1925, p. 338). I have previously described a P. calcarius
(1915, p. 320) which Puymaly referred to Prasiola leprosa Kútz. (Puy-
maly 1920, p. 189) and which is no doubt identical with the P. vulgaris
of Chodat and Brand, or at any rate with a number of the forms
which these autliors refer to the species. In my paper (1915) I deflned
the difference between P. calcarius and P.vulgaris, the former of which
undoubtedly shows afíinity with Prasiola while the latter is evidently
different. Neither Brand nor Chodat seem to distinguish between
these two forms, and only a closer study of them, coupled with a study
of Meneghini’s original text, figures, and specimens will be able to
clear up the matter.
Myrmecia pyriformis Boye P. n. sp.
Cellulis junioribus globosis, diam. 5 p, vel ovalibus, long. 9 p, lat. 5p,
Cellulis adultis pyriformihus ad lignum afíixis, long. 16—24 p, lat. 15—
20 ju; membrana chlorozincico jodurato coerulescente, parte exteriore plus
minus incrassata. Chromatophoro parietali, pyrenoide instructo. Zoo-