A local network?

  

Net-of-Cords Kelp (Dictyoneurum californicum) 

Note the interesting reticulated or network-like patterning.  The blade was in the process of splitting into two through the center.

Dictyoneurum has a distinctive holdfast -- strap-shaped, with haptera (branching root-like structures) on both sides.

 

 

[This kelp had washed ashore, so I placed it on a rock to take a photo, but this kelp lives much lower in the intertidal zone.]