HOW TO KNOW THE SEAWEEDS 



23b Gonimoblast placenta of small cells, without nutritive filaments 

 extending into the pericarp. Fig. 39 GracilaTiopsis 



Figure 39 



Fig. 39. Gracilariopsis sjoestedtii (Kylin) Dawson 



A vertical section through a mature cystocarp showing the small- 

 celled, dense gonimoblast placenta and the absence of nutritive fila- 

 ments connecting with the pericarp. This species occurs along the 

 Pacific Coast from central Oregon southward and has been identi- 

 fied from North Carolina and Florida by the writer. It should be 

 pointed out that this plant and Gracilana venucosa are indistinguish- 

 able except with regard to the cystocarps and antheridia which in 

 the former are superficial and in the latter are produced in deep 

 pocket-hke cavities. One other species of Gracilariopsis occurs com- 

 monly along the southern California coast, G. andersonii (Grunow) 

 Dawson. It is relatively short and tufted. 



43 



