HOW TO KNOW THE SEAWEEDS 



97b Solid axes bearing hollow, cylindrical, constricted branchlets with 

 diaphragms at the constrictions. Fig. 132 .. Gasfrocionium coulteri 



Fig. 132. Gastroclonium coulteri (Harvey) Ky- 

 lin 



A small upper portion of a plant to show 

 the solid axis and the hollow, constricted, lat- 

 eral branchlets, X 1.6. Frequent on rocks 

 along virtually the entire Pacific Coast. The 

 degree of development of the hollow lateral 

 branchlets varies so that one should expect 

 occasionally to find specimens in which these 

 are scanty, much reduced, or otherwise in- 

 conspicuous. Close inspection, however, will 

 invariably reveal the transverse septa at the 

 constrictions in some of these hollow branch- 

 lets. 



Figure 132 



98a Thallus with a single large, hollow bulb (pneumatocyst) at the 

 end of a long, unbranched stipe (See Fig. 134) 99 



98b Plants with more than one hollow structure, 



100 



101 



