57. 
58. 
59. 
Go. 
61. 
62. 
63. 
64. 
65. 
66. 
CHECKLIST OF THE FERNS. 317 
PHEGOPTERIS Fee. 
Phegopteris Dryopteris Fee. 
Phegopteris Dryopteris Robertiana Dav. 
Phegopteris Calcarea Fee. 
Phegopteris hexagonoptera Fee. 
Phegopteris polypodioides Fee. 
Phegopterts Phegopter’s Underw. 
POLYPODIUM L. 
Polypodium ineanim Sw. 
Polypodium polypodtordes Hitchcock. 
Polypodium vulgare L. 
Polypodium vulgare f. Cambricum Willd. 
Polypodium vulgare f. biserratiim Millspaugh, 
Polypodium vulgare oreophilum Maxon. 
Polypodium vulgare deceptum Maxon, 
POLYSTICHUM Roth. 
Polystichwm acrostichoides Schott. 
Aspidium acrostichoides Sw. 
Dryopterts acrostichotdes Kuntze. 
Polystichum acrostichoides f. incisiwm Underw, 
Polystichum acrostichoides f. crispune Clute. 
Polystichum Braunii Lawson. 
Aspidium aculeatum Braun Doéll. 
Dryopterts Braunzd Underw. 
Polystichum tonchitis Roth. 
Aspidium lonchitis Sw. 
Dryopterts lonchités Kuntze. 
PTERIS L. 
Pteris aquilina L. 
Pteridium aquilinum Kuhn, 
Pteris aquilina pseudocaudata Clute. 
Pterts aguilina caudata Hook. 
