81 
As two-thirds of the species described below are new, and as I have several 
new observations on most of the formerly described species, it might be useful to 
make here some general remarks on the genus Chantransia, based on the obser- 
vations communicated below. 
As shown by Borner (1904), the structure and development of the basal por- 
tion of the frond within the genus Chantransia offers considerable differences which 
can be used in subdividing the genus. I fully agree with this excellent phycologist 
who by his small but important paper has largely contributed to the classification 
of this genus. If my classification does not always coincide with that of Dr. Borner, 
it depends on the fact that I have not found representatives for all the subdivisions 
of Bornet in the Danish waters, and that I have found new species which do not 
fall under these groups. I may now give an account of the types found by me. 
In some species the germinating spore is a globular or hemispherical basal 
cell which keeps its form and divides only on branching. This cell is fastened to 
the substratum by a cementing substance staining intensely blue by Mayer’s Hæ- 
malum'. In some cases it gives off only free filaments (first group), in others it 
also produces endophytic filaments from its under side (BoRNET’s second group, of 
which no representative is mentioned below). In Ch. efflorescens (fig. 61) and Ch. 
Thuretii (figs. 30, 31) the hemispherical basal cell gives off an erect filament and 
several radiating, creeping, epiphytic filaments which later unite to a pseudoparen- 
chymatous disc giving off a number of erect filaments. During this development 
the original basal cell becomes indistinguishable amongst the other cells of the 
basal disc. I believe that the basal part of the frond probably develops in a similar 
manner in some other species, the germination of which has not been observed 
(Ch. attenuata, stricta, Daviesii). In a small group of species (Ch. polyblasta (fig. 43) 
and Ch. humilis (fig. 44)), to which may be added the partly endophytic species 
Ch. Dumontie (fig. 52) and Ch. cytophaga (fig. 50), the germinating spore is divided 
before ramification by a vertical wall into two cells of equal size each growing out 
in a creeping filament, which branches and forms a filamentous basal structure; 
in the central part of this the filaments may later fuse together, while a large 
number of relatively short erect filaments are given off from their upper side. In 
Ch. virgatula (incl. secundata) the germinating spore is usually divided by 3 excen- 
tric walls into 4 cells forming a parenchymatous disc, which for some time keeps 
this character during continued divisions of the cells, while later on some of the 
marginal cells may grow out into creeping filaments (figs. 37—41). In Ch. leptonema 
the development begins in the same manner, but the parenchymatous stage is very 
short, the disc at an early stage growing out into long creeping filaments (fig. 48). 
In Ch. Macula the basal disc behaves in a somewhat similar manner as in CA. vir- 
gatula, but the erect filaments are much reduced or wanting, the sporangia being 
1 This substance attains an extraordinarily great development in Ch. microscopica var. collopoda 
Rosenv. (Deux. Mém. Alg. mar. Groenl., Medd. om Grenl. XX, 1898, p. 11). which, however, does not belong 
to Ch. miscroscopica Neg. but ought to be regarded as a distinct species, Ch. collopoda Rosenv. 
D. K. D. Vidensk. Selsk. Skr., 7. Række, naturvidensk, og mathem. Afd. VII. 1. 11 
