332 
VASCULAR CRYPTOGAMS. 
Key to Natural Orders. 
1, Small floating plants or land 
plants with — quadrifoliate 
ea 5. Rhizocarpeae (p. 359). 
Land plants, never with quadri- 
foliate leaves 2. 
2, Stems hollow, wit rithout "leaves, 
branches whorled with sheaths 
at the joints . 2. Equisetaceae (p. 357). 
Stems solid; with leaves. (except 
Psilotum), branches not whorled 3. 
scale-like and imbricate l. Filices. 
. Leaves scale-like, imbricate, with 
a single central vein .. ee 4, 
4. Leaves all round the stem and 
usually uniform 3. Lycopodiaceae(p. 351 ). 
Leaves in four rows and. dimor- 
phous .. “an es 4. Selaginellaceae(p. 358). 
1.—FILICES. 
Key to genera. 
l. Capsules with a complete ring ... 2. 
ing of capsules incomplete or 0, 
climbing or aquatic fern or 
fronds over 6 feet long or 
fertile and leafy parts distinct 31. 
2. a peules with a transverse ring 
reeping or translucent fera 3. 
anaes with a vertical ring — ... 5. 
3. Involucre absent; stem 7 ng 
ous ; creeping fern... -- l. Gleichenia (p. 334). 
Involucre cup-shaped ; stem not 
ichotomous ; translucent fern 4, 
4. Hair-like receptacle prolonged 
Eee the involucre... 6. Trichomanes (p. 335). 
Regine apt not , prolonged beyond 
e involu 9. Hymenophyllum (p. 
335). 
5. e present ... ee ss 6. 
Involucre absent 22, 
6. Involucre holding | the “capsules 
st the fronds 8. 
Involucre i: the capsules 
es the fronds ... J t x 
- Trunk spiny sd. im aE I P oos (p. 334 
Trunk not spiny ... ees s ksonia (p. 335). 
