Proc. Roil. Socij. (if El/ ill. ] 



[Vol. XXX. 



Fia. 21. — Another view of the vegetation I)ordering the river, from a ])Osition 

 close to that of fig. 20, showing the zone of Castalia sjteciosa, amongst which 

 are a few stems of Equisetum limosum and Scirjius lacustris ; beyond this 

 zone, Carex rostrata appeal's as in the preceding picture. 





Fig. 22. — A view looking into the zone of Carex rostrata which hnrdcrs the' 



river, as shown in the two preceding ligiires. 



Mk George West. [Plate U.—Kt/encI to on page 115, 



