392. 
are usually 25—28 w long, 14—19 w broad. The longest sporangium which was met 
with (Middelfart, April) measured 36 w in length. The sporangium is first divided 
Fig. 330. 
Rhodochorton Rothii. Parts of upright filaments with upright and 
descending or creeping branches. In E regeneration of loosened 
filament by formation of descending filaments. 270 : 1. 
by a transversal wall, afterwards 
by two longitudinal ones. The spor- 
angia are probably produced in 
autumn; they were found ripe in 
the months January to May, empty 
in June. In specimens collected at 
Bornholm as late as August a 
few sporangia were still present, 
while the greater part had emptied 
and were fallen off. And specimens 
found by LYNGBYE near Hesselg in 
the southern Kattegat in July 1832, 
growing on Phyllophora Brodiei, 
still bore ripe sporangia. During and 
after the fructification new long 
erect branches may be produced 
from the sporangial cluster, between 
and under the sporangia, growing 
out to a bundle of long filaments. 
The erect filaments attain only 
a length of 6mm. Mr. Boye PE- 
TERSEN has, however, given me 
a specimen gathered at Middelfart 
in the beginning of July, measuring 
17 mm. It reminds one very much 
of Rh.intermedium KJELLMAN (Spetsb. 
mar. klorof. Thallof. I, 1875, p. 28, 
Nor. Ish. Algfl. 1883, p. 231 pl. 15 
fig. 8), which possibly is not speci- 
fically distinct from Rh. Rothü. As 
the specimen in question is sterile, 
a closer comparison with KJELL- 
MAN'S plant cannot be made. 
R. Rothü is perennial. It occurs 
principally in the littoral zone be- 
tween middle and low-water mark, 
but it has also been found in the sublittoral zone to a depth of 36 m; in this zone, 
however, it does not occur so abundantly as in the littoral zone. In exposed places 
on the rocky coast of Bornholm and the neighbouring Christiansø it may ascend 2 
or 3 meters above the sea level, usually associated with Verrucaria maura and 
