HOW TO KNOW THE SEAWEEDS 



72b Erect filaments of two kinds: crowded, short, moniliiorm filaments 

 below, and long, straight, free filaments extending above; plants 

 epiphytic. Fig. 104 Elachista 



Fig. 104. Elachista fucicola (Velley) Areschoug 



A very small bit of a sterile tuft showing the 

 two kinds of filaments, X 80. This is a common 

 epiphyte on coarse algae from New Jersey north- 

 ward and from central Oregon northward. Two 

 other species occur on the New England coast on 

 Chondrus, Ascophyllum, and other coarse algae. 

 The tufts are small, usually under 2 cm. high, but 

 are often abundant and conspicuous. 



Figure 104 



73a Reproductive organs in a series in the middle of a filament. Fig. 

 105 Pylaiella 



Figure 105 



Fig. 105. Pylaiella litoralis (Linnaeus) Kjellman 



A small portion of a fertile filament showing the serial and inter- 

 calary production of unilocular sporangia, X 180. Commonly 5-25 cm. 

 long on various substrates from New Jersey northward and from cen- 

 tral California northward along the Pacific. Other species may occur, 



but are rare or of local distribution. 



J 



81 



