Flora of the Northwest Coast 



PHYLUM I. PTERIDOPHYTA. Fern Plants. 



Plant containing woody tissue and vessels in the stem 

 and producing spores asexually which, on germination, 

 develop very small structures called prothallia, on which 

 are borne the sexual reproductive organs from which the 

 asexual plant is developed. The sexual plant is rarely 

 collected, and the classification is based mainly on the 

 characters of the asexual plant. 



■ Class I. FILICINEAE. 



Plant highly organized, vascular, with green usually 

 large leaves; spores borne within the tissue of, or in modi- 

 fied hairs on, modified or unmodified foliage leaves; stem 

 solid, underground (in ours). 



Family 1. POLYPODIACEAE. Fern Family. 



Sporangia stalked, surrounded by a more or less complete 



vertical annulus and bursting transversely; fruit dots on the 



backs or the margins of the leaves, with or without indusia. 



Indusium none. 



Fruit dots usually linear, obscured by a powder 



on the under surface of the leaf. \. Ceropteris, 2. 



Fruit dots roundish, not obscured by a powder. 



Leaves entire or simply pinnate. 2. Polypodium, 2. 



Leaves bipinnatifid or ternate. 3. Phegopteris, 3. 



Indusiun:. present. 



Fruit dots with marginal false indusia formed of 

 the more or less altered edge of the leaf. 

 Sporangia on a marginal vein which connects 



the ends of the lateral veins. 4. Pteridium, 4. 



Sporangia at or near the ends of unconnected 

 veins. 

 False indusium continuous. 5. Cryptogramma, 4. 



False indusium not continuous. 



Fruit dots large, on a reflexed portion 



of the margin of the leaf. 6. Adiantum, 4. 



Fruit clots minute, finally running 

 together and covering the leaf- 

 2 I 



