(Gi 
ously branched frond bearing at the top of the branches bunches of radiating small, 
narrow shoots which must be considered as sterilized sexual shoots. These loose 
forms are probaby able to vegetate and propagate for a long time by continued growth 
and branching, a multiplication taking place by decay of the oldest parts of the frond. 
Ahnfeltia plicata, which, like the foregoing species, is of common occurrence 
in the Danish waters, also appears in a loose form (f. tenuior, p. 568), which is 
easy to recognize as belonging to this species but, on the other hand, of a very 
aberrant shape. Its frond is lower and thinner and the branches divaricate. It is 
common in company with other loose Algæ, in particular between Zostera. It is 
undoubtedly able to vegetate and propagate by continued dichotomizing and dividing. 
Gracilaria confervoides occurs, attached to stones, in the Danish waters only 
on the shores of the North Sea and Skagerak, but loose specimens have been met 
with in a few places in the inner Danish waters. A few specimens, not different 
from the normal ones except by being destitute of base were found in the Limfjord, 
where they may easily have been introduced by currents from the North Sea. It 
is more remarkable that loose specimens of the same species have been carried by 
the currents to two localities in the inner waters situated at great distances from 
those where the species is normally growing. At Hofmansgave, at the North coast 
of the island of Funen, loose specimens differing from the normal ones only by some- 
what curved branches, but otherwise easily identified by their anatomical structure, 
were met with in the years 1824 to 1828. They must have originated from spec- 
imens introduced by currents from the Skagerak and have kept vegetating at least 
in that period. Later they have not been observed and have probably sooner or 
later decayed owing to the unfavourable external conditions. The specimens found 
at the north coast of Møen, where the salinily of the water is very low (about 8 "/oo), 
are more aberrant in the inconsiderable size and small thickness of the fronds; the 
anatomical structure of the frond, however, showed with certainty that the fronds 
belonged to Gracilaria confervoides. The fact that the loose specimens were found 
in a considerable number in this locality suggests that this form f. {enuissima is 
able to vegetate and to propagate by dividing, and it can be concluded that it has 
been adapted to keep alive during a certain period. Whether it would be able to 
propagate for an indefinite period must be settled by later investigations. 
The most remarkable example of loose Florideæ taking a shape very aberrant 
from that of the typical species is Phyllophora epiphylla f. Bangii (p. 540), characterized 
by its incised frond. It has so far been considered as an independent species, 
referred even by one author to another genus (Rhizophyllis). By examining a great 
number of specimens of Phyllophora Bangii I have been able to prove that it is a 
loose form of Ph. epiphylla, connected with it by rare transitional forms. The typical 
species only occurs in the North Sea, Skagerak and the Northern and Eastern 
Kattegat, whereas f. Bangii almost exclusively occurs out of this area in water of 
lower salinity in the inner Danish waters, including the Western Baltic. That it has 
not been met with in Øresund is probably due to the too low salinity ol the 
78* 
