A GIGANTIC KELP. 31 



"So many interesting points are connected with the l Ma- 

 crocyslis Pyrifera' 1 that ' a book might be instructively filled 

 with its history; while its economy, and the myriads of liv- 

 ing creatures that depend on it for food, attachment, shel- 

 ter, and means of transport, constitute so extensive a field 

 of research, that the mind of a philosopher might shrink from 

 the task of describing them." * 



It has been stated by previous authors that this 

 seaweed had been found upwards of 1000 feet in 

 length, but this Sir Joseph Hooker thinks is probably 

 exaggerated. At the Crozet islands however he ob- 

 served extensive beds of it, growing in water 40 fa- 

 thoms deep, yet with the tops streaming a long distance 

 along the surface. He estimated the length of these 

 great weeds at about 7 oo feet, but admits that " the 

 elongation of ' Macrocystis Pyrifera' may be inde- 

 finite. " f He then gives some interesting details as to 

 its value to seamen, and states 



" It is, where growing, not only the infallible sign of sunken 

 rocks, but every rock that can prove dangerous to a ship is 

 conspicuously buoyed by its slender stem and green fronds, 

 and we may safely affirm that without its presence many 

 channels would be impracticable, and many harbours in the 

 south closed to our adventurous mariners." "This gigantic 

 weed," according to Sir J. Hooker, "is subject to every 

 vicissitude of climate, and literally ranges from the antarctic 

 to the arctic circle." 



Mr. Darwin, in his " Naturalist's Voyage " also gives 

 very similar details, and was evidently greatly struck by 

 the extraordinary properties of this remarkable plant. 



* Botany of the Antarctic Voyage of H.M. Discovery Ships Erebus 

 find Terror, under Captain Sir James Clark Ross, by Sir Joseph D. 

 Hooker, 6 Vols; Vol. i., p. 465. 



t Ibid., p. 461. 



Ibid., p. 463. 



