278 NOTES ON THE BOTANY 
lected, show that a very long time must and that ages may 
have elapsed since these floating portions left the parent 
plant. This Weed did not make its appearance close to the 
ice, still less in that open water which exists to the south- 
ward of the Packs. An accurate list was kept of the ships’ 
position and dates of the time when it was found, and highly 
curious it was to note how uniformly the plant seemed to 
fail when the temperature of the water fell below 32? or 32^, 
in whatever latitude that might be, and how it appeared to 
avoid the icebergs; 633° is the highest south latitude at 
which it was seen. 
The currents that transport these weeds, are very slow 
indeed; probably wind-currents, which, with the send of the 
sea, must have wafted the original parent stock from the 
southern portions of New Zealand and the smaller islands 
appertaining to it, as far as Cape Horn. Its propagation in 
the water is apparently exceedingly tardy, and may possibly 
be effected by the agency of marine animals, which swarm 
about the patches of this and the Laminaria, their sole vege- 
table refuge in the higher latitudes. No roots whatever have 
been traced in such circumstances, nor do they seem essen- 
tial to its life and increase. After separating out a single 
plant, perhaps thirty fathoms long, one end was invariably 
found green, and the other gradually more and more en- 
crusted with Flustre, Serpule and Bicellarie, Sponges, &c.5 
till it terminated abruptly; the cellular substance of the stem 
being quite exposed, not covered with any more condensed 
parenchyme, but apparently bitten off; while here and there, 
along the stem, there were often piecestaken out, apparently 
by some molluscous animal. 
One of the officers of H.M. schooner Arrow, a very intel- 
ligent individual, has stated it as his opinion, founded on the 
examination of many specimens, that as the Macrocystis 
grows large, it finally weighs up the stone which was Its 
moorings, and then the whole plant goes off to sea, which, 
as he conceives, explains the reason for so much being found 
alive in the ocean. 
