POLYPODIACEAE. 



16. NOTHOLAENA R. Br. Prodr. Fl. Nov. Holl. i: 145. 1810. 



Mostly small rock-loving ferns, with i-3-pinnate or pinnatifid leaves and marginal 

 roundish or oblong sori, which are at first distinct but soon confluent into a narrow band. 

 Indusium none, but the sporanges are sometimes at first covered by the inflexed margin of 

 the leaf. Veins free. Sporanges pedicelled, provided with a vertical transversely bursting 

 ring. Lower surface of the leaf often covered with a white or yellow waxy powder, or in 

 some species with a dense tomentum. [Greek, in allusion to the woolly lower surfaces.] 



About 40 species, of wide distribution, most numerous in America. Besides the following, 

 some 13 others are found in the mountainous portions of the southwestern United .States. 



i. Notholaena nivea dealbata 



(Pursh) Daveup. Powdery 



Xotholaena. (Fig. 70.) 



Clieilanthes dealbata Pursh, Fl. Am. Sept. 



671. 1814. 

 Xolholaena dealbata Kunze, Amer. Journ. Sci. 



(II.) 6: 82. 1848. 

 Xotholaena nivea var. dealbata Davenp. Cat. 



Davenp. Herb. Suppl. 44. 1883. 



Rootstock short, chaffy with narrow 

 brown scales. Stipes tufted, wiry, very 

 slender, shining, dark brown, i^'long; 

 leaves triangular-ovate in outline, acute, 

 broadest at the base, i / ~4 / long, 3~4-pinnate, 

 the rachis black and shining ; pinnae 

 ovate, the lower slender-stalked ; ultimate 

 pinnules ovate or obovate, obtuse, lobed, 

 crenate or entire, small, scarcely i" long, 

 white and powdery on the lower surface. 



On calcareous rocks, Missouri and Kansas 

 to Arizona and Texas. June-Sept. The typ- 

 ical form of the species occurs in the South- 

 western States and in Central America. 



17. POLYPODIUM L. Sp. PI. 1082. 1753. 



Pinnate or simple ferns with stipes articulated to the creeping rootstocks. Sori circular, 

 dorsal, in one or more rows on either side of the midribs. Indusium none. Sporanges pedi- 

 celled, provided with a vertical ring which bursts transversely. Veins variously arranged. 

 [Greek, in allusion to the branched rootstocks of some species.] 



About 350 species, of very wide geographic distribution, mostly of tropical regions. Besides 

 the following, 5 occur in Florida, i in Arizona and 3 on the Pacific Coast. 

 Lower surface of the leaf glabrous; plant green. i. P. vulgare. 



Lower surface of the leaf densely scaly; plant grayish. 2. P. polypodioides. 



i. Polypodium vulgare L,. Com- 

 mon Polypody. (Fig. 71.) 



Polypodium vulgare 1,. Sp. PI. 1085. 1753. 



Rootstock slender, widely creeping, dense- 

 ly covered with cinnamon-colored scales. 

 Stipes light colored, glabrous, 2'-6' long; 

 leaves ovate-oblong or narrowly oblong in 

 outline, subcoriaceous, evergreen, glabrous 

 on both surfaces, 3 / -io / long, i'-3' wide, cut 

 nearly to the rachis into entire or slightly 

 toothed, obtuse or subaeute, linear or linear- 

 oblong segments; sori large, borne about 

 midway between the midrib and margins of 

 the segments ; veins free. 



^ On rocks or rocky banks, almost throughout 

 North America, Asia and Europe. Ascends to 

 5600 ft. in Virginia. The leaf varies much in 

 serration. Forms with the- ends of the segments 

 t nl.irged, somewhat palmately lobed, and the 

 upper crested are known as var. cristatum. 

 |J with the segments broad and deeply pin- 

 natifid are called var. Cambricum. Summer. 



