ROOTS OF SEA-WEEDS. 85 



than as separate organs contributing to the nourishment 

 of the body. With this end in view, Nature furnishes 

 sea-weeds, in the great majority of instances, with a 

 simple conical disc, by which they strongly adhere to the 

 smoothest surface ; and when a more root-like holdfast 



is given, it is merely a multiplication of such discs, or 

 a strengthening by lateral ropes the original gripe taken 

 of the rock. Roots of this nature may be seen in the 

 large Oar-weeds (Laminarice) of our coasts, particularly 

 in the L. digitata, a species with a long cylindrical 

 walking-stick stem, crowned with a broad leaf, cloven 

 into a great number of ribbon-like segments. In this 

 plant, while young, the root consists of a few rudimen- 

 tary processes : as it advances in growth, and as new 

 props are required to support the additional weight, the 

 branches of the root lengthen and others are gradually 

 added, till a compact mass of interwoven fibres is formed, 



