HOW TO KNOW THE SEAWEEDS 



along the California coast where L. pacifica KyUn is the most wide- 

 spread and abundant one. Flattened species of Lauiencia key out un- 

 der step 181a (See Fig. 226). 



Figure 64 



38a Thallus gelatinous and slippery; cortex of short, free filaments with 

 large terminal cells. Fig. 65 Sphaerotrichia divaricata 



Fig. 65. Sphaerotrichia di- 

 varicata (C. Agardh) 

 KyUn 



A. The apex of a plant 

 highly magnified to show 

 the enlarged apical cell, 

 X 560. B. A small portion 

 of a transection of a thal- 

 lus to show the free corti- 

 cal filaments with their 

 large terminal cells, X 

 200. The structural fea- 

 tures .of this plant and 

 other such gelatinous 

 forms are usually best ob- 

 served by crushing out terminal portions of branches on a sHde. Com- 

 monly epiphytic on larger algae during the summer from New Jersey 

 northward. Some forms tend to be hollow. 



B 



Figure ^5 



59 



