THE SHIELD (AND BUCKLER) 

 EERNS. 



THE ALPINE SHIELD FEKN, 



on HOLLY FEEN. 

 Polystichum Lonchitis* BOTH. 



POLYSTICHUM is an extensive genus 

 of the group of Aspidiese ; and con- 

 sists for the most part of harsh 

 spiny evergreen ferns, scattered 

 from the torrid to the frigid zone, 

 but represented in this country 

 by only three species : Poly- 

 stichwti Lonchitis, Polystichum 

 aculeatiim, and Polystichum angu- 

 lare. These species, however, are 

 veiy variable, and so closely con- 

 nected by intermediate [forms that 

 it is difficult sometimes to distin- 

 guish their exact limits. 

 The Alpine Shield^Fern is one of the rarer ferns, 

 taking its other name of Holly Fern from its hard 

 and prickly appearance. It is an evergreen, (with a 



* The Polypodium Lonchitis of Linmeus. 



