FLOWERING PLANTS AND FERNS OF ARIZONA 27 



1. Sori submarginal or the sporangia borne in naked lines along the veins (11). 

 11. Sporangia following the veins throughout (12). 



12. Blades densely ceraceous beneath 11. Pityrogramma. 



12. Blades conspicuously hairy 12. Bommeria. 



11. Sporangia borne at or near apex of the veins (13). 



13. Plants large, coarse; sporangia borne on a veinlike receptacle connecting 



the vein ends 13. Pteridium. 



13. Plants mostly small and rock-loving; sporangia not borne on a special 

 transverse receptacle (14). 

 14. Sporangia borne on under side of sharply reflexed membranous lobes 



of the leaf 14. Adiaxtum. 



14. Sporangia not borne on the back of reflexed lobes (15). 



15. Vein ends distinctly thickened; proper marginal indusium often 



present 15. Cheilaxthe-. 



15. Vein ends scarcely or not at all enlarged; proper membranous 

 indusium invariably wanting (16). 

 16. Margin of segments widely reflexed or revolute, usually modified; 



blades glabrous or nearly so 16. Pellaea. 



16. Margin of segments narrowly or not at all revolute; blades 

 variously hairy, paleaceous, or ceraceous beneath. 



17. NOTHOLAEXA. 



1. WOODSIA 



Small rock ferns, the rhizomes tufted; fronds many, fasciculate, 

 suberect; blades linear to lance-ovate, 1- to 2-pinnate, the segments 

 lobed or pinnatifid, hairy or subglabrous, free-veined; sori dorsal, 

 roundish, often confluent with age; indusia inferior in attachment, the 

 spreading divisions cleft to filiform, often concealed at maturity. 



Key to the species 



1. Blades bearing numerous flexuous, flaccid, hyaline, septate hairs beneath. 



1. W. SCOPULIXA. 

 1. Blades devoid of flexuous septate hairs (2). 



2. Indusia ample, consisting normally of a few short, broad, concave lobes; 



blades obviously glandular-pubescent 2. W. pluhmebae. 



2. Indusia consisting of hairlikc segments; blades glabrous or nearly so (3). 

 3. Segments of indusium numerous, truly capillary, flaccid, greatly exceeding 

 the sporangia: leaf tissue coriaceous; segments sharply dentate, with 

 whitish-crustose margins, the teeth ending in several hairlike processes. 



3. W. MEXICAXA. 



3. Segments of indusia few, short, turgid, moniliform from a broader base, 

 often obscure at maturity; leaf segments herbaceous, the margins not 

 altered 4. W. oregaxa. 



1. Woodsia scopulina D. C. Eaton, Canad. Xat. II. 2: 90. 1S65. 

 Recorded for Arizona on the basis of a collection purporting to be 



from the Huachuca Mountains (Lernmon in 1882) and one from "Mari- 

 copa" (Pringle in 1882). Quebec to the Great Lakes region and Alaska, 

 southward to western Oklahoma, Colorado, Arizona, and California: 

 also northwestern Virginia to western North Carolina and eastern 

 Tennessee. 



2. Woodsia plummerae Lernmon, Bot. Gaz. 7: 6. 1892. 



Woodsia obtusa var. glcuuhilom D. C. Eaton and Faxon, 

 Torrey Bot. Club Bui. 9: 50. 1882. 



Springerville (Apache County), Kaibab Forest (Coconino County), 

 to the mountains of Cochise, Santa Cruz, Pima, and Yuma Counties, 

 2,000 to 9,000 feet; shaded ledges and cliffs. Western Texas to Ari- 

 zona and northern Mexico. 



