456 
stem, but in the latter, however, only in the basal and not in the 
inflated part. I have now examined the stem and especially the 
basal part of the stem of numerous specimens of L. fceroensis 
without, however, finding the least indication of muciparous canals 
which are doubtless wanting here, though they are distinctly de¬ 
veloped in the lamina and exactly resemble those which Kjell- 
man found in L. saccharina and figured in N. I., pp. 292—3 (234—5), 
tab. 25, fig. 7. 
The length of the stem varies considerably according to whether 
the plant grows in shallow or deep water; thus, at the head of 
Kalbakfjord in quite shallow water — a few feet — I found spe¬ 
cimens with lamina measuring 3—4 feet and the stem hardly a 
foot long, while in normally developed specimens the stem and 
the lamina are of about Ihe same length; in L. longicruris , however, 
the stem is reported to be generally longer than the lamina. With 
regard to the hollowness of the stem, it appears as if it often 
extended for a greater distance. I have closely examined a large 
example, the stem of which measured somewhat above 2 metres, 
and found that it was already hollow at the apex just below the 
lamina, and this hollow expansion widened rapidly so that a few 
inches from the apex of the stem it attained to a diameter of about 
one inch and remained this width for a short distance; this inflated 
part, being tilled with air, serves to buoy up the lamina. When 
growing in shallow water (1—2 metres), which seems to be the 
favourite habitat of this plant, these inflated apical parts of the 
stem may be seen in abundance floating about on the surface and 
bearing the immense lamina which hang thence downwards towards 
the bottom. The hollow part gradually narrows towards the base, 
and a foot above it the stem becomes solid. In young specimens 
the stem is solid. The haptera are long, thin, and very much divided. 
In typical, well-developed specimens the lamina is broadly el¬ 
liptic, has a distinctly cordate base, a strongly waved margin, and 
sometimes tapers somewhat to the top giving almost an ovate 
appearance to the lamina. In young specimens the lamina is nar¬ 
rower, oblong elliptic, with base less distinctly cordate, and often 
agrees well with Harvey’s figure of L. longicruris in Nereis Boreali- 
Americ., Part 1, tab. IV and in Phycol. Brit., Vol. Ill, tab. 339. On 
the other hand, the lamina in typical, well-developed L. longicruris, 
judging both by the specimens from Greenland and other places 
preserved in the museum in Copenhagen and by the figures and 
