120 OUR NATIVE PERNS AND THEIR ALLIES. 



conspicuous or wanting ; sori, 10 in each valve. (M. macropus 

 A. Br.) Texas, New Mexico. 



** Sporocarps i (rarely 2) on each peduncle. 

 3. M. uncinata A. Br. Plant 620 cm. high; leaflets 

 nearly smooth, entire, 10 16 mm. long ; sporocarps 6 mm. wide, 

 8 mm. long ; peduncles 15 30 mm. long, 2 4 times the length 

 of the sporocarps ; raphe long, terminating in two approximate 

 teeth, the upper longer and mostly uncinately curved; sori, 

 13 14 in each valve. Western Louisiana (Hale), Dallas. 

 Texas (Reverchon}. 



L2L*/ _ 4. M. vestita Hook. & Grev. Plant 3 6 cm. high; leaf- 

 lets entire or slightly toothed ; sporocarps 4 7 mm. long, 3 5 

 mm. wide; raphe short, lower tooth short and blunt, the upper 

 acute, a little longer, sometimes curved ; paleae varying from 

 soft, dense and spreading to short and appressed, in mucronata 

 forms, where it is sometimes wanting; sori, 6 11 in each valve, 

 a very variable species. (Includes M. mucronata A. Br.) Ar- 

 kansas (Nuttall), Kansas ( Watson}, Texas, Arizona (Lemmori), 

 California, Nevada ( Watson}, Oregon (Hall), Washington, Mon- 

 tana Watson), Dakota (Nicollet), Florida (Underwood}. 



Var. tenuifolia (Engelm.) Unde. & Cook. Plant slender, 

 5 15 cm. high; leaflets narrow (2 4 mm. wide), more or less 

 falcate, the apex often somewhat truncate and unequally 

 toothed, villose with appressed hairs ; sporocarps single, 5 8 

 mm. long, 4 5 mm. wide, the teeth divergent, subequal ; sori, 

 9 ii in each valve. (M. tenuifolia Engelm. and former 

 edition.) Pierdenales, Texas (Lindheimer), Western Texas 

 (Wright). 



'ii. PILULARIA L. PILLWORT. 



Sporocarps globose, longitudinally 2 4 celled, dehiscent from 

 the apex; cells with parietal cushions bearing in the upper por- 

 tion microsporangia and below these numerous rnacrosporangia 

 contain ing solitary macrospores. Leaves filiform from a slender 

 creeping rootstock, the sporocarps subsessile or peduncled or 

 in the axils of the leaves. Named from Lat. pilula, a pellet. 

 Includes six species widely distributed. 



. i. P. Americana A. Br. Leaves setiform, I'long; sporo- 

 carps i" in diameter, attached by the side to a short, descend- 



