Fig. 103 Lessonia. A, adult plants of L. flavicans. B, C, sporeling 

 stages in L. nigrescetis. (After Oltmanns.) 



although, of course, there is no connexion. The stipe of L. flavicans 

 is extremely stout and rigid, 5-10 ft. long and sometimes as thick as 

 a human thigh, the additional growth being due to a deeper seated 

 secondary cortical meristem. It appears to be more or less regularly 

 branched in a dichotomous fashion, a feature which is brought 

 about by the lamina being sUt down successively to the intercalary 

 growing region, each successive segment developing into a new 

 lamina with its own portion of stipe. Dried parts of the stipe, which 

 can easily be taken for pieces of driftwood, are used by natives to 

 make knife handles. This method of causing splitting should be 

 compared with the other processes found in Nereocystis, Macro- 

 cystis and Postelsia (cf. below). 



Lessoniaceae : P(95^^/5/a (after A. Postels). Fig. 104 



This is a monotypic genus, often known as the *sea palm', that is 

 confined to the Pacific coast of North America where it grows 

 between Vancouver Island and central CaHfornia on rocks which 

 are exposed to heavy surf. The smooth, glossy, cylindrical stipe is 

 thick but not very long, up to i m. in height. It is erect and hollow 

 within and bears at its apex a number of short, soUd, dichotomously 



183 



