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MELANOSPERMEZ. 25 
summer or early autumn, while the larger kinds seem to prefer the winter 
months. The rapidity of growth observable in some of the larger species 
during the winter is truly 
surprising. A remarkable in- 
stance is related by the cele- 
brated civil engineer, George 
Stephenson, who, in the 
autumn of 1813, was employed 
to erect a stone beacon: on 
the Carr Rock, at the entrance 
of the Frith of Forth. .The 
workmen, having cleared the 
rock of the seaweed .growing 
upon it, chiselled the surface 
to prepare it for the masonry. 
On the approach of winter, 
operations were suspended 
until the May of the following 
year, when, to the surprise 
of the workmen, the rock was 
found to be again covered with 
seaweed. Most of the plants 
of the new crop were of the genus Alaria, many of which were from 4ft. 
to 6ft. in length, all of which must have been the growth of about eight 
Fig, 48. Laminarw bulbosu. 
Fie. 49. Chorda filum. Fig. 50. Alaria esculenta. 
months, from the time that the very minute seeds had vegetated on 
the newly cut sandstone rock. I have often observed instances equally 
