ALG^. 83 



it is stated of it that " specimens measuring between 

 one hundred and two hundred feet are common in the 

 open ocean, and these are always broken off at the 

 lower end, either from the division of the frond by 

 sea animals, through whose agency the plant increases 

 and the floating island it forms dilates, or from the 

 impossibility of securing the whole mass from the 

 motion of the vessel or the swell of the sea, in lati- 

 tudes where no boat can be lowered. Again, D'Ur- 

 ville, upon whose observations in natural history the 

 utmost reliance may be placed, states it to grow in 

 eight, ten, and even fifteen 'brasses' of water, from 

 which depth it ascends obliquely, and floats along the 

 surface nearly as far ; this gives a length of two 

 hundred feet. In the Falkland Islands, Cape Horn, 

 and Kerguelen's Land, where all the harbours are so 

 belted with its masses that a boat can hardly be 

 forced through, it generally rises from eight to twelve- 

 fathom water, and the fronds extend upwards of one 

 hundred feet upon the surface. We seldom, however, 

 had opportunities of measuring the largest specimens, 

 though washed up entire on the shore ; for on the 

 outer coasts of the Falkland Islands, where the beach 

 is lined for miles with entangled cables of Macro- 

 cystis, much thicker than the human body, and 

 twined of innumerable strands of stems coiled together 

 by the rolling action of the surf, no one succeeded in 

 unravelling from the mass any one piece upwards of 

 seventy or eighty feet long : as well might we attempt 

 to ascertain the length of hemp fibre by unlaying a 

 cable. In Kerguelen's Land the length of some of 

 the pieces which grew in the middle of Christmas 



