GUIDE 



GROUP II 



FERTILE FRONDS PARTIALLY LEAF-LIKE, THE FERTILE PORTION 

 UNLIKE THE REST OF THE FROND 



[The species coming under the genera Botrychium and Ophio- 

 glossum may appear to belong to Group I, as the fertile and the 

 sterile portions of their fronds may seem to the uninitiated like sep 

 arate 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, pinnag 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 pinnae 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 di- 

 vided leaf with three primary divisions ; 1-2 pinnate. Fertile por 

 tion a branching fruit-cluster. In rich woods. P. 80. 



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