GUIDE
FERTILE FRONDS PARTIALLY LEAF-LIKE, THE FERTILE PORTION UNLIKE THE REST OF THE FROND
[The species coming under the genera Botrychium and Ophioglossum may appear to belong to Group I, as the fertile and the sterile portions of their fronds may seem to the uninitiated like separate fronds, but in reality they belong to the one frond.]
5. ROYAL FERN
Osmunda regalis
Large. Sterile fronds twice-pinnate, pinnules oblong. Fertile fronds leaf-like below, sporangia in clusters at their summits. In wet places. P. 67.
6. INTERRUPTED FERN
Osmunda Claytoniana
Large. Sterile fronds once-pinnate, pinnæ pinnatifid. Fertile fronds leaf-like above and below, contracted in the middle with brown fruit-clusters. In wet places. P. 72.
7. CLIMBING FERN
Lygodium palmatum
Climbing, with lobed, palmate pinnæ and terminal fruit-clusters. Moist thickets and open woods. Rare. P. 75.
8. ADDER'S TONGUE
Ophioglossum vulgatum
Small. Sterile portion an ovate leaf. Fertile portion a slender spike. In moist meadows. P. 77.
9. RATTLESNAKE FERN
Botrychium Virginianum
Rather large. Sterile portion a thin, spreading, ternately divided leaf with three primary divisions; 1–2 pinnate. Fertile portion a branching fruit-cluster. In rich woods. P. 80.
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