HOW TO KNOW THE SEAWEEDS 



181a Branches each with an apical pit (See Figs. 18C; 56) in which the 

 growing point is situated. Fig. 227 Laurencia (in part) 



Figure- 227 



Fig. 227. Two examples of flattened species of Laurencia: A, L. diego- 

 ensis Dawson, B, L. splendens Hollenberg, both occurring in south- 

 ern California, X 0.75. 



Perhaps the commonest of the flattened laurencias within our ter- 

 ritory is L. spectabilis Postels & Ruprecht which is similar to L. diego- 

 ensis, reaches a height of 20 cm. or more, and occurs from central Cali- 

 fornia northward. No flattened species of this genus seem to occur 

 commonly along any part of the Atlantic coast, although cyHndrical 

 species may be found. See step 37b. 



1811? Branches without an apical pit, although in Gelidium sometimes 

 the apex is somewhat indented 182 



171 



