Rit Landbúnaðardeildar : B-flokkur - 01.05.1947, Side 8

6
South-Sweden. During the last summer research was carried out on
rather large material of C. edentula from the south- east beaches of the bay
Faxaflói in South-West of Iceland. That material was fixedin Carnoy 3:1 and
stained in acetic-orcein (cf. Darlington and La Cour, 1942) and smeared
in the same way as described by Löve (1943). The results of the investiga-
tion are given below.
2. Cytological results.
a. Cakile maritima L.
The European species C. maritima was found to be diploid with
2n = 18, n = 9 chromosomes in our material from South-Sweden. The
same number had previously heen determined by Wulff (1937) in
material from Schleswig-Holstein and by Hagerup (1941) in inaterial
from Denmark. Our observations were made on root-tips, but no examina-
tions were made by the present writers of the ineiotic hehaviour of this
species.
b. Cakile edentula (Bigel.) Hook.
The chromosome number of the Icelandic material of C. edentula was
found to be 2n = 36, n = 18, i.e. the species is to be regarded as a
tetraploid.
The meiotic behaviour was examined rather thoroughly, although no
observation was made on the earlier stages of prophase, as the material
was not easily stained at these stages in acetic-orcein. Good slides were
obtained at diakinesis and the following stages, but only few observations
were made at the stages before metaphase-I. At diakinesis the bivalents
are mainly united by one or two chiasmata, and some few multivalents
were found in every cell studied. The terminalization was complete or
almost complete.
At metaphase-I most of the chromosomes are found as bivalents but
in every cell studied there were one or more quadrivalents observable.
Analysis of metaphase-I in side-view is not difficult in the material if
studied iinmediately, but as the slides were not thoroughly analysed at
once, only a relatively low number of cells were totally investigated.
In Fig. 1 a typical metaphase-I with 4 quadrivalents is shown, and
in Fig. 2 five quadrivalents from another cell are depicted. A metaphase-I
plate with two quadrivalents in polar view is shown in Fig. 3. The chromo-
some pairing was analysed in 294 cells with the results given in Table 1.
As shown in that table univalents are observed in only 6 cells, i.e. in about