450 T. Holm — Studies in the Cyperacece. 



This sheath is, as we have stated above, not especially charac- 

 teristic of any type of Fimbristylis \ it is common to our 

 native species and a number from the old world. It is not 

 restricted either to any certain shape of leaf or to'species from 

 any peculiar region or locality. Furthermore the relative 

 development of the mechanical tissue in our genus from dry 

 as well as from wet soil furnishes no information regarding a 

 supposed existence of plant-societies with xerophytic or hydro- 

 phytic structures ; neither the radial arrangement of the pali- 

 sade-cells or the presence of a parenchyma-sheath. Hence an 

 attempt to classify our native species of Fimbristylis as 

 " xerophytes or hydrophytes" would seem very unnatural 

 and not in conformity with their biological peculiarities. 



Brookland, D. 0., December, 1898. 



