HOW TO KNOW THE SEAWEEDS 



76b Asexual plants bearing polysporangia. Fig. 110. . . .Pleonosporium 



Figure 1 10 



Fig. 110. Pleonosporium dasyoides (J. Agardh) De Toni 



A. A small upper part of a sterile plant showing the regular, alter- 

 nate branching, X 56. B. A polysporangium,. X 72. This is our larg- 

 est member of the genus, reaching 20 cm. in height along the central 

 Cahfornia coast. The somewhat smaller P. horreri (J. E. Smith) NdgeU 

 occurs from Florida to Cape Cod. Several other relatively local species 

 may be found along the Pacific Coast. 



86 



