97 
Artificial Key based on non-technical characters; awnbers 
rs les refer to generic nusbers. 
w O fa.Sterile and fertile fronds of different form, the sterile green, 
jparsley-like, the ultimate segments flat with toothed margins, 
F / the fertile taller, yellowish, the ultimate segments inrolled, 
| \ 
the margins without teeth 6 Cryptogramma crispa 
o /b.Sterile and fertile fronds of similar or even identical form or outline 
2 Frond palmately compound into a symmetrical spray by forking of 
(, stipe into 2 subequal l-sided divisions 7e Adiantum pedatum 
”, Frond pinnately compound (sometimes basal segment of lowermost 
( pinna disproportionately long, giving a false-palmate aspect) 
4 2a.Frond ternate with 3 er divisions, the whole as broad as long 
® or nearly so (triangular to pentagonal or obliquely deltoid) 
‘, Frond of thick texture, the margins inrolled; steaks oe 
5. Pteridium aquilinum 
o Frond of thin texture, plane; pinnae opposite 1, Phegopteris Dryopteris 
“, 4.6.Frond distinctly longer than broad in outline 
‘ 3a.Frond strictly pinnate, the pinnae alternate 
& Pinnae upwardly lobed or eared at base; stipe and rachis 
/?, chaffy with shining red-brow papery scales 
/Q Fronds short-stiped, the lowermost pinnae suborbicular, 
14 unlike the principal median pinnae 10. Polystichum lonchitis 
j- Fronds distinctly stiped, the lowermost pinnae falcate-lanceolate, 
/q like the principal median pinnae 10, Polystichum mmitum 
© Pinnae not lobeds stipe smooth or but little)and rachis not at all 
lal 
ey So 2- Polypodium vulgare 
is 
an So 
i, 3b Frond twice- to thrice-pinnately compound 
8 4aFronds mostly less than 20 cm, longs; stipe and rachis shining 
‘nd to light brovm; ferns of moderately to strongly 
sumny habitats . 
/O Fronds granulate-glandular and ciliate beneath 11. Woodsia scopuling 
