Abstract
#1. Luzula campestris (L) DC. as described in Buchenau's Monograph
of the Juncaceae is morphologically very diverse; to the
twenty varieties described in this work, six more have been
added since 1906.
#2. The geographical distributions of these taxa are different;
many of them overlap, but some cover only a very limited area.
#3. The taxa found in Europe are ecologically separated* Their
morphology has been more closely examined, and they are found
to fall into six quite distinct groups: sudetica, pallescens,
campestris, multiflora, campestris and congesta. A small
proportion of plants could not be assigned to any taxon, and
must be considered as possible hybrids or as intermediate
forms.
The flowering time of campestris is two or three months
before that of the other taxa.
#4. Three of the taxa are very common in Britain: campestris,
multiflora and congesta. They are ecologically separated,
campestris growing in dry grassland, multiflora in woods
and congesta in moors and bogs.
#5. Detailed examination of the morphology of these three taxa
shows that they remain more or less distinct in the field, but
that they do merge into each other to some extent. The number
of plants intermediate between congesta and multiflora is much
greater than the number between campestris and either of them.
#6. The three taxa mentioned above were grown under identical
conditions in the experimental garden. The morphological
differences were maintained in the floral characters, and
the differences between campestris and the other taxa in the
vegetative characters were emphasised.
#7. Chromosome counts were obtained from seedlings and from
plants grown in cultivation. The numbers obtained were: -
pallescens 2n = 12 diploid;
campestris 2n = 12 diploid;
multiflora 2n = 36 hexaploid;
con fiesta 2n = 48 octoploid;
multiflora x congesta 2n = 42 heptaploid.
#8. The evidence from the morphology, ecology and cytology of the
British material suggests that specific rank should be given
to all three.
#9. If (campestris) multiflora and con esta are recognised at
specific rank, it seems to be reasonable that most of the
other varieties should receive the same treatment. Specific
rank is therefore proposed for all the varieties of L. campestris
in Buchenau, with the exception of flaccida, debilis and calabra,
of which insufficient material was available. Specific rank
is also recommended for L, echinata, L. bulbosa and probably
also for L. kobaysii, L. k;jelimnnniana and L. cusickii.
#10. Although the taxa warrant specific rank, some recognition
of their affinities should be made. They should perhaps
therefore be considered as an aggregate species, L. campestris
agg., which is composed of a polyploid complex of related
species.
