606 
washed ashore by violent storms. The specimens from these localities are only 
slightly different from the typical ones except that they are all without base and 
sterile, and it can be added that they are all devoid of hyaline 
hairs. They are about 12 cm long, and the branches are often 
somewhat bent. Horman BANG referred them to Fucus scorpioides 
Fl. Dan. t. 887. LyNGBYE was much in doubt as to their deter- 
mination. The anatomical structure agrees with that of Gracilaria 
confervoides, in particular the central tissue built up of large short 
cells, by which this species is easily distinguished from Furcellaria 
fastigiata and Ahnfeltia plicata with which the loose specimens 
have been compared. 
Loose specimens were further met with in two localities in 
the Limfjord, where they occurred on clay-muddy bottom without 
vegetation. These specimens are only different from the normal 
Fig. 609. ones by the want of base and by being sterile. 
Gracilaria confervoides F. tenuissima. A more aberrant sterile, loose form has been 
f. tenuissima. Ulfsund, 
Soren Lund. Nat. size. 
gathered by Mr. Soren Lunp by dredging in Ulfsund on the north 
side of the island of Mgen at 3 metres’ depth, where it occurred 
in company with loose Cladophora. The specimens are only 2—3.5 cm long and very 
thin, 140—200 w in diameter, while in the normal specimens the main axis often reaches 
a thickness approaching to one mm. At the first glance it did not seem easy to determine 
these thin specimens, but an examination of the anatomical structure 
showed that they must be referred to Gracilaria confervoides. The 
medullary tissue of the terete frond consists of large, almost isodia- 
metrical cells without rhizoids, not lengthened in the longitudinal direc- 
tion of the frond, and the tip of the frond agrees perfectly with that of 
the normal frond, being only somewhat thinner. The apical meristem 
was decidedly active in spring. The fronds have a brown-red colour; 
they have a firm consistency and are repeatedly branched; 7 generations 
of shoots were observed. The branches of the consecutive generations 
are essentially of the same thickness, the youngest branches only some- 
what thinner. The branches are more divaricate than in the typical 
specimens. — It seems probable that these much reduced specimens 
derive from detached normal specimens accidentally introduced from 
the Skagerak in these waters in olden time, having been able to 
keep alive and vegetate in a sterile state by adaptation to the 
Fig. 610. 
Gracilaria confer- 
voides f. tenuissima. 
Tip of frond. 70:1. 
local external 
conditions, especially the low salinity which probably varies about 1 p. ct. 
Locality. Sm: Ulfsund, off Nymarke Nakke, 600 m from land (S. Lund, April 1930). 
